Details//Speculation from PAX East:
"Gideon narrates shown, vess shown, chandra, garruk, [sorin], jace. Gideon says I have made allies out of my [enemies]" - @pureval on M12 video
"Sorin and gideon in m12 #mtg" - @dantack on same video
"They will not consider changing the #commander posion rule until after action is out and all of the posion cards are released." - @pureval
"5 Different Commander decks will be available this summer (June). Full 100 card decks, at least 18 rares, & 51 unique cards. #mtg #PaxEast" - @Wizards_Magic (Not New Info) (precon-commander decks to be released)
5 Commanders will be 3-Color Wedge Legends and 2-Color Enemy Color Legends
"New commander sets not considered collectible will be on the shelf for a while." - @pureval
Nin, the Pain Artist - UR (Rare)
Legendary Creature - Vedalken Wizard
XUR, T: ~this~ deals X damage to target creature. That creature's controller draws X cards.
1/1
http://twitpic.com/48l0y7
http://twitpic.com/48l0yg
http://twitpic.com/48l0yc
I'll post more as more is available.