Here's my main hope for Abrams's Star Wars: he dumps John Williams as the composer (using the SW theme and opening, of course; Disney will mandate that) and films the thing in a faster paced and more modern style.
I think it's a safe bet Michael Giacchino will do the music, although I can't imagine Williams not being asked or turned down. Williams will probably just step aside. It's a new regime. Giacchino would probably keep the main and end title music and then do his own thing, while keeping it "Star Warsy." Abrams will also most likely bring a brand new look to the franchise since he doesn't have Lucas's "everyone on vitural sets" stiffness. Whether one likes his visual style or not, it DOES have energy. He may keep it closer to the original trilogy style than Star Trek, but he'll bring his own pacing and energy to the project. There may be a feeling that since it's "episode 7" they want to keep the look close to what had come before, but who knows?
I see nothing but good things for Star Wars, honestly.
Considering Lucas is apparently so anal about Star Wars that he wants 20th Century Fox to distribute Episode VII just so it'll have the same logo at the start that Episodes I-VI had, I'm not so sure he'll allow Abrams to deviate too much from the style of days gone by.