Been playing Mass Effect 2 and I'm kind of disappointed. It's basically KotOR without the Star Wars universe. Same gameplay, similar battle system, similar "force" powers.
I'm not sure if I like the mission gameplay either. In KotOR, you'd get a mission that was somewhat elaborate and involved some searching and back and forth. So far in ME2, missions consist of someone telling you to go do something, you walk into the next room where the target is sitting and deal with him, then walk back into the previous room to report that you completed the mission. Maybe the missions get more complex later, but so far it's pretty silly.