In PvE, Ghostcrawler mentions that Blizzard is mostly happy with the tank classes and notes that while healers do have it a bit hard, this is intentional. Heroics are meant to be a challenge. As for DPS, he offered that some classes, such as arcane mages and marksman and beast mastery hunters, are too low in their damage, while others, such as shadow priests and fire and frost mages, are being watched closely before final judgment is made on their numbers.
In PvP, Ghostcrawler says Blizzard is satisfied with the decreased emphasis on healing prevention and burst damage. Crowd control and dispel mechanics, especially offensive dispels, may see some PvP nerfs, and priests will specifically be getting some PvP buffs.
Stats also got some mention. A lot of stats are being neglected by some classes, and the dev team wants to fix this. Mastery will be either buffed or completely revamped for many specs, such as unholy death knights and retribution paladins. Haste may be made to scale with more attacks, such as Lacerate, Slam, and Steady Shot, in order to make the stat more desirable to certain specs.
Check after the break for the complete text of Ghostcrawler's post, including a list of specifically planned (but not finalized) class changes for future patches.