I don't like the idea of playing a Mass Effect game and not allowing me to make any choices to affect my mass.
Seriously though, the limited option thing sounds weak.
What drew me to the game was the ability to alter
something nearly every 2nd/3rd line of speech.
I heard beforehand there are 3 (or so) ways to play the game, pertaining to cutscenes and stuff. Action, Story and RPG (or something) each of which changes the amount of work you as the game-player put into actually playing the game. I'm not sure if that's just their way of saying "easy, normal, difficult" for this game. I kind of assume so.
Anyways, I finally beat ME2 last night. So I guess I should experience the third one at some point soon.