After the Ultimate Marvel vs. Capcom 3 finals at SoCal Regionals, a new trailer debuted for Ultra Street Fighter IV that introduces a new mechanic: Edition Select. Each edition of Street Fighter IV brought forth some changes between different characters in the form of various nerfs and buffs. Now you get to decide which edition of which character you can play as.
For instance, one of the exhibition matches at SoCal Regionals saw Mike Ross using the Super Street Fighter IV version of E. Honda while Gamerbee used the original Street Fighter IV version of Sagat, complete with only being able to select one Ultra for Sagat. In other words, the limitations from whatever edition you choose are there. Can't wait to see how many people go for Street Fighter IV Sagat come June. More info can be found at Shoryuken.com.