I know a lot of people that hated Saw, but I actually loved it. I love movies that make me think. I'm always trying to figure out "who done it" and usually have it figured out pretty quick. With Saw, I was completely baffled.
I went to see Saw 2 last night. LOVED it! It is pretty gory, but that is right up my alley. So, for those that liked the first, you should safely like part 2. I was worried that it would suck since it was a sequel, but I really liked it.