Finished ME2 5 times already, really liked the combat system, much better than ME1 but story is much shorter, much buggy, more teammates but some are quite useless, and completely useless when playing on hardcore/insanity mode >_>
finished the insanity mode with soldier class, m-98 widow sniper rifle + Heightened adrenaline rush = pwnage

really liked the background musci too, just incase you guys wanna listen the music without going play the game:
http://www.ea.com/music/mass-effect-2-official-soundtrack

well if you let the mp3 play untill the end, each songs, the mp3 are actually stored on your browser cache, clear the cache before streaming the song,
after that you can obtain the playable mp3 from your browser cache, this is how i got the ost for FREE

Yeah, i like the Grunt, Tali, Thane, and the Jack's background music too.