Look here "now"

Rating: 8/10 (24 February 2008)

It's not necessary to have seen the first saw to enjoy this movie, but it always helps. You would be familiar with the concept of the movie and get into the movie quicker. If you haven't seen SAW, then you'll be in for a surprise. Especially as they did up the ante (the gore section of it in particular).
This one is as the rest of the franchise, not for the faint-hearted! It's not subtle, it's in your face. And although one could argue that there is not a big deal of plot here, it is about other things (like the tension it builds up). If you like your gory movies delivered with tension and a big thrill element, than you can't go wrong with this one!