You know what I'm really excited about? The way the reputation system works.
http://blog.bioware.com/2012/03/01/reputation-in-mass-effect-3/
In ME2 you were essentially part of a zero-sum system where if you mixed your actions then you wouldn't be able to get the highest Intimidate/Charm options. THis is more like a return to the ME1 system, where your reputation on the whole isn't dependent on single actions, and you can use any Charm/Intimidate you like. So long as the Galaxy knows you're a bad-ass, you can do almost anything.
It's going to be an exciting time for people who like the role-playing aspect of the game.