My roommate bought this when it first came out then let it to me since non of his PCs can run it shortly after and I finally decided to install it this weekend to test it out.
Some general impressions.
The game runs badly, I've got a AMD 64 chip (about a 2 gig processor), 1.5 gigs of RAM and a Gforce 6600 (256megs of ram) and the game barely runs and yet it looks like a PS2 game, and not even a good one for that. The music skips all the time, the cutscenes skip, heck the intro movie which is pre-rendered skips and barely plays. However actual combat and exploring isn't bad, doesn't tend to slow down. This is on the lowest settings for the game too, which is sad since I can run Oblivion at almost max on everything (just have to turn of one of the shadow types and lower the amount of grass, this game won't even display shadows for me) so it's fairly obvious that Obsidian never got around to optimizing their code, which is sad. Also Camera controls suck unless you've got a 3rd button on your mouse (I've got a clickwheel that you can push in for a 3rd button but it doesn't work despite the game saying it should) and so you have to use the arrow keys or move the mouse off screen to rotate.
So far just about everything else, except character creation which this series is still about 10 years behind on, is an improvement over NWN 1, though the Voice Acting is still kind of cheese/bad. But I just can't get over those system requirements and how badly it runs on anything but a $4,000 PC. I'll probably do a full review of it later on, but so far I like it more then NWN 1 story wise.