Edit 2: World of Raids is currently keeping an updated list as the 2.3 info continues to come out:
Worldofraids forums :: 2.3 Unofficial Patch Notes, Changes and Daily Blue

Edit: When going back to include the volumous amounts of new information that was made available after this was originally posted, I saw that a fairly comprehensive list was being maintained on the official forums. Forthwith, a link:
WoW Forums -> 2.3 "Official" Patch Notes


Several bits of juicy 2.3 info dropped today:

General

- Zul'Aman is complete and now only needs time on the PTR.


Shaman

- Frost shock no longer subject to diminishing returns.
- Shamanistic Rage will also reduce all damage taken by 30% for its 30 second duration.
- Spirit Weapons will also reduce melee threat by a total of 30% rather than 15%. This is intended to affect both white and yellow damage.
- Two-handed weapons will be trainable
- Replacing the two-handed weapon talent will be Elemental Focus, which places the shaman in a "focused state" after landing a melee critical strike. The focused state will reduce the mana cost of the shaman's next shock spell by 60%.
- Mental Quickness will also add 10/20/30% of your AP to your +damage/healing.
- New relics to be added which will support all talent trees (includes Druids and Paladins)


Rogue

- Blind will no longer require a reagent. It will also be changed to a ranged physical attack, will share the same diminish category as Cyclone, and diminish in PvE as well as PvP. It will no longer be considered a poison.


Priest

- Pain Suppression will be able to be cast on a friendly target and will reduce the target's threat by 5% and reduce their damage taken by 40%. The cooldown will be reduced to 2 minutes.
- Meditation will be increased to 10/20/30% mana regen.
- Power Word: Shield will gain additional benefit from spell damage and healing bonuses. Base absorb values for ranks 10, 11 and 12 have been reduced to compensate for this change.

The Shaman changes look incredible. I thought they were only upping spirit weapons to 20% from 15%?

Source

That's kinda stupid. Show me a source. 'til then, i don't believe you.

WoW Forums -> The lack of change has been noticed........

Edit: It would be great if people stopped shitting up the thread with "OMFG I don't believe u" and just spent 2 seconds on BlueTracker or the WoW forums to find it themselves.

Crusader Strike is being changed back to 6 second cooldown.

Source.

Forums de wow-europe.com -> Les Cendres d'Alar ont été dropé

Blue post on the French forums regarding a new flying mount available from Cenarion Expedition at Exalted for 2000g in 2.3.

Blind no longer a poison...is it safe to assume it will no longer be cleanseable then?

W ... T ... F ...

These two changes are larger than any priests have ever received in any talent review ... and they're being randomly done in the shaman/rogue patch? Please provide a link to the blue "hint" toward these things, because they're immensely huge changes to the mechanics of the priest class. The meditation one in particular is one we've been asking for since ... Nef died, and we all realized that T2 would be with us forever due to its 3-piece bonus.

WoW Forums -> Enhancement shaman - Low blow

I am guessing that they'll have to reduce the snare duration because otherwise we're back to the good ol' 'snare lasts longer than cooldown' problem back from frost shock 1.0. Either that or they'll have to seriously increase the mana cost.

The paladins were told quite emphatically (pre-2.2) that their ret changes were being pushed off until 2.4, since 2.3 would be primarily concerned with rogues & shamans. When did they decide to change it to "everyone gets some changes"?