The specific game rules are up and available for viewing on evo2k.com.
RE: SSFIV Ruleset
If one of the players asks for a blind pick, then P1 must tell the judge his character and ultra selection. P2 then must pick his characters, and after that P1 must pick the characters he told the judge. Everything is blind pick.
As far as the winner switching ultras, since ultras can counter the other player’s ultras, the winner will NOT be allowed to switch up any ultra. There should be no advantages given to the player that already is up a game in the set.
A perfect example of ultras countering ultras, is Seth vs Chun Li, if Seth picks Ultra 1, Chun Li can punish Seth’s Ultra 1 when blocked from full screen away, even though in many player’s eyes, Ultra 2 is way better.
UPDATE We are thinking about letting the winner change ultra but they have to pick their ultra first in game 2 or 3. Thoughts??