I absolutely loved ME2. I'm still playing it. Actually created a good-looking female Shepard who is ruthless. And by shooter, I mean, combat seemed like a big box level every time. I've killed many an enemy without a bullet. There's nothing more satisfying than whipping multiple enemies against a wall after lifting them into the air.
And I enjoy the conversation options. Scanning planets, however, even though I was excited at first blush, is for the birds.
Yes, there are consequences to every action, yes you can influence your fate, and those of others and yes there are role-play possibilities, but, it just isn't immersive as F3 and ES4, for me. You can only pull out your weapon at certain points, there is a definite difference between those types of interactions, I guess the problem is that there isn't enough of a fluid transfer from a peacetime event, to a battle event. I like how in Fallout 3, there are sometimes explosive transitions from friends to instant enemies.