Ha! I found a several video long, complete soundtrack of BW2! Major spoilers here too. Here's a link to the music, starting with the Team Plasma Leader's theme.
http://www.youtube.com/watch?v=9EybTIUgjs8&feature=relmfuNOW, HERE IS THE SPOILERS. SPPOOILLEERRRSSSS.Ghetsis is a bit cooky now. His theme is much more frenetic. Other then aging, depicted by his shorter, less green hair and Plasma cane, he is also found a new, yet still Egyptian-ish, decor. It's black, and no longer looking like the rook from chess. From his battle sprite in Giant Chasm, he stabs the blunt-ended cane into the hard, frozen ground using only his rage at you. Yeah, no wonder he tried to
SPOILER kill you
END SPOILER. Other then that, N is officially not gay, but badass as he stops his old man from killing you, and flying in on Reshiram or Zekrom's back.
BIG SPOILERYou cannot catch White/ Black Kyruem in the first encounter
END BIG SPOILER.The God Stone is still not available, although the item used to make Black/White Kyurem is called the DNA Link Pin, confirmed not to be the God Stone. Now Iris is champion, HUGE SHOCKER, and a little older, meaning that all characters from the previous game have aged. The E4, by my knowledge, has not changed. Archoma, officially named Corless, is the only Professer that is young and handsome affiliated with an evil Team. There is a Hard/Easy mode, depending which game you pick. Easy Mode is in White, while Hard Mode is in Black. An internal key, after defeating Iris, unlocks the Hard/Easy Mode, thus making it needed to play the game, not needing a code, to unlock these modes.
Oh yeah, Cheren is a Gym Leader, which I'm sure most of you know.