I realize I'm posting this about 2 weeks after everyone else.  I gave myself some time to look into the changes and try to wrap my head around them before I said anything.  Even after some time, deliberation, and reading other people's takes, I'm still not thrilled.  I'm entirely underwhelmed on the mage front.  There's really no part of the announced Cata changes that makes me want to cheer.  But, let's start from the beginning anyway.

"Flame Orb (available at level 81): Inspired by Prince Taldaram's abilities in Ahn'kahet and Icecrown Citadel, this spell allows the mage to cast a flaming orb that travels in front in a straight line, sending beams that cause fire damage to passing targets. Once it's cast, the mage is free to begin casting other spells as the Flame Orb travels. While the spell will be useful to any spec, Fire mages will have talents that improve it, possibly causing the Flame Orb to explode when it reaches its destination."
From what I've seen in Old Kingdom and ICC Blood wing, these are two pretty different spells.  So I'm kind of wondering where the heck they're going with this.  In OK, Taldaram tosses out a Flame Orb that splits into several orbs and shoots anyone in range with lasers emanating from both orbs.  The described spell is nothing like that.  It's the ICC Blood wing one.  In ICC, he tosses out one big Orb that targets a single person and splits off little lasers to each person that gets in it's path, diminishing the total power of the big orb when it hits its target.  I've never been a fan of fire, but this might be an interesting spell.  It really depends on how much power Blizzard puts into the big orb.  There was a later blue post that said it was a casted but not channeled spell, which is good because that would completely make it useless.

"Time Warp (level 83): Grants a passive Haste effect much like Bloodlust or Heroism to party or raid members. It also temporarily increases the mage's own movement speed. Time Warp will be exclusive with Bloodlust and Heroism, meaning you can't benefit from both if you've got the Exhaustion debuff, though the movement-speed increase will still work even when under the effects of Exhaustion."
Everyone is so excited about this change, but I'm not.  I know people were whining and complaining about only one class having Bloodlust, but don't people know they can do content without it?  Sure it's a useful tool, but there are teams out there without it that finish content just fine.

I know what you're thinking.  They're trying to make things more fair for raiders so no one gets special treatment to come along.  And now that's more reasons to bring a mage!  Well that's all well and good, but here are the potential problems I see.  The movement speed thing is nice, but tying it to the Haste spell also ties you to timing.  Anybody that raids regularly knows you don't just blow bloodlust when you feel like it.  There are specific times when it's used in encounters.  That being said, if you need to move out of fire, don't go reaching for Time Warp if you're not already Sated.  I suppose this really depends on the cooldown they give us on the spell.  If it's shorter than BL/H then it may end up being more useful, but it's still restricted by that timing.

As for the spell itself... my biggest problem with this is that Blizzard didn't even put any thought into giving us a new cool spell.  They gave us recycled material in the first two "new spells."  UNDER.  WHELMED.

"Wall of Fog (level 85): Creates a line of frost in front of the mage, 30 yards from end to end. Enemies who cross the line are snared and take damage. The mana cost will be designed to make Wall of Fog efficient against groups, not individuals. This spell is intended to give mages a way to help control the battlefield, whether the mage is damaging incoming enemies (Blizzard can be channeled on top of Wall of Fog) or protecting a flag in a Battleground. 10-second duration. 30-second cooldown."
This looks like it might be a nice spell for PVP, but it's completely useless in PVE unless you're afraid of adds in a dungeon.  That's a hell of a lot of aggro to absorb from a pack though.  I was hoping for something a little more frosty for a Frost Tree spell.  I know they said they were changing the focus back to BGs in Cata instead of arena, but I have fleeting interest in them at best... so again, not excited.

That's it for the new Spells.  Now on to the next part:  mechanic changes.

"Arcane Missiles is being redesigned to become a proc-based spell. Whenever the mage does damage with any spell, there is a chance for Arcane Missiles to become available, similar to how the warrior's Overpower works. The damage and mana cost of this spell will be reworked to make it very desirable to use when available. This change should make gameplay more dynamic for the mage, particularly at low levels."
Last I checked, AM was pretty much already a proc-based spell if you're playing Arcane with any efficiency.  You only really pop AM once you have missile barrage proc, otherwise you're punching Arcane Blast over and over again to build your stacks.  There have been those annoying moments for me when I can't get an MB proc to save my life and I'll go ahead and hit missiles.  So I guess my question to Blizzard is are they going to handle the proc the same way they did missile barrage?  WoW.com's mage columnist brought up a good point in that the spell will be more available to Frost/Fire mages, but unless they also switch some of the talents around, they'll still probably get better damage out of another spell.  Depending on how much haste you have, it still takes time to cast missile barrage.

"We are planning to remove spells that don't have a clear purpose. Amplify Magic, Dampen Magic, Fire Ward, and Frost Ward are being removed from the game, and we may remove more."
Why, yes, Blizzard.  Those spells are useless.  JUST LIKE INCANTER'S ABSORPTION.  You're taking away two potential uses for that useless talent and nerfing it even more.  For the record, I specced out of it when the patch dropped so I wasn't using it anyway.  I generally can't risk the loss of mana from mana shield to get the buff.  Rolling Arcane Blast usually takes enough of that as is. I could really care less to see any of these spells go.  So it's fine that they're cleaning that out of my spell book.

"The ability to conjure food and water will not become available until higher levels (likely around level 40), as we're making changes to ensure mages generally won't run out of mana at lower levels. Once mages learn how to conjure food and water, the conjured item will restore both health and mana."
This kinda sucks for lowbie mages.  I remember leveling and pushing through my mana pool like a hyper kid with a rocket pack and constantly sitting to drink in dungeons while other classes could keep going and got annoyed with waiting on me.  Granted, I don't have to deal with that as I have a max level mage, but still, its kind of depressing for anyone who thought they might be interested in the class come Cata.  I am glad they're combining them to mana and health food though.  Summoning a bajillion stacks of both at low levels took up a lot of valuable bag space.

"Scorch will provide a damage bonus to the mage's fire spells. Our goal is for Scorch to be part of the mage's rotation and a useful damage-dealing ability, even if someone else is supplying the group with the spell Critical Strike debuff. Scorch will provide the mage with more specific benefits, which can also be improved through talents."
So basically Scorch is going to be Improved Scorch?  And they're going to change the talents dealing with this?  Sounds great if you're a fire mage and you're bored with your rotation.

"Arcane Focus will now return mana for each spell that fails to hit your target, including Arcane Missiles that fail to launch. We want Arcane mages to have several talents that play off of how much mana the character has and give the player enough tools to manage mana."
So I want to know who went and got all the Mage Programmers drunk the night before this stuff was due and then thought it'd be a great idea to add this in?  Are they trying to alleviate our need for hit and encourage us not to hit cap?  Is this their grand idea on how to fix our mana regen?  To be honest with you, I don't have an issue with mana regen unless I die and my evocate isn't up when I get battle rezzed.  The short cooldown on Evocate in a standard Arcane Spec does not make it difficult to use it as much as you need it.  The part that makes me the most nervous is where they say "ncluding Arcane Missiles that fail to launch."  Are they adding something in to nerf missiles?  If they are that leaves Arcane mages with ONE reliable spell in their rotation.  Who cares if you get some mana back if you don't do any damage?

"The talent Playing with Fire will reduce the cooldown of Blast Wave when hit by a melee attack, instead of its current effect."
So a cooldown reduction instead of damage and no extra damage taken.  Again, a fire thing.  So not sure how I feel about it.

"Pyromaniac will grant Haste when three or more targets are getting damaged by the effects of your damage-over-time (DoT) fire spells."
Are we eliminating the old Pyromaniac?  Assuming so, that's decreased crit and mana regen.  Hast is good, but that limits this to an AOE only talent.  Blargh.

"The Burnout talent will allow mages to cast spells using health when they run out of mana."
An interesting mechanic and a good way to piss your healers off.  I have to tell you that one of my pet peeves as a healer is when a warlock eats him or herself for mana and then doesn't bother to fill his health pool back up again, expecting me to use my mana pool to fill it instead.  It's just not courteous.  Hopefully this will just be a back up plan for when Evocation is on cooldown.  Not a reason to have no mana pool at all and just keep casting through and hoping your healer keeps you up.  Mages are notoriously squishy.  This makes fire mages even squishier.

On to Mastery:

Spell damage
Spell Haste
Mana Adept:
Arcane will deal damage based how much mana the mage has. For example, Arcane mages will do much more damage at 100% mana than at 50% mana. If they begin to get low on mana, they will likely want to use an ability or mechanic to bring their mana up to increase their damage."
The drunk mage programmers are at it again.  So basically what they're saying is to get the full potential out of your character's damage, you need to keep your mana pool filled the majority of the time.  Wait... I forgot.  Doesn't casting decrease your mana pool?  So should I stop casting?  Is this just a push for us to use Evocate and Mana gems more?  I suppose the big question on this one is how it will scale.  Are we going to be doing 50% damage at 50% mana?  This also pulls into focus our aggro:  if we have a damage bonus at 100% mana, then we're going to be VERY bursty and so will our aggro.  We might have to actually start waiting for 5 sunders again on boss fights.  This would make more sense to me in reverse - lower mana = more damage.  That'd be a reason for mages to balance their mana pool and damage output.  It'd also encourage us to bust through our pool faster and keep casting rather than to stop and refill the pool more often.

Spell damage
Spell Crit
All direct-damage fire spells will add a damage-over-time (DoT) component when cast. The flavor will be similar to how Fireball works; however, the DoT component will be much stronger."
So fire mages are warlocks now?  Congratulations.  Makes sense since they took focus magic and made it a warlock/mage conspiracy.

Spell damage
Spell Crit damage
Casting Frostbolt places a buff on the mage that increases the damage for all frost, fire, and arcane spells. The only damage spell that won't be affected by this buff is Frostbolt."
Last I checked, a Frost PVE rotation pretty much contains two spells:  Frostbolt and Deep Freeze.  Are they trying to throw in other frost spells as well?  It doesn't seem like this would make Frost any more viable for raiding than it already is, and this makes me sad.

I know this is just a preliminary preview.  I realize things can change between now and Cata and I hope they do.  I'm really hoping Blizzard has some other tricks up their sleeve to whip out and surprise us in a good way because right now, the mage is not looking so good for Cataclysm.