This game makes me feel like a better gamer.
I think that in most games, I'm crippled by my min/maxing compulsion. Right now for example, I'm halfway through KotOR 2 and loving it, I think most would think I'm ruining my play by constantly alt-tabbing out to make sure I'm not missing opportunities to gain influence with my guys.
Bioshock 2 is so freeing: is this what it's like for regular people to play video games?
I fill up on the good ammo, which makes me allowed to use it. I fill up with money, which lets (makes!) me spend it. I know I won't buy all those tonics so I only have to buy the ones I want.
In a million little ways, this game scratched my RPG itch in ways that are new to me.