The first one is fantastic. It has become my favorite game. I still haven't played through as dark side yet.
...one of these days.
I'm pretty much a buy any Star Wars game person, so I'll probably get KOTORII as well. I just may hold off for awhile unless the reviews are outrageously good. At this point, I'm not expecting it to have much innovation or that 'zing' like the first one.