I saw it yesterday. Theater was packed and I had to get tix in advance, this movie is making a killing. I thought it was pretty good- great bloody fight scenes. And unlike other movies, it didn't take long to get into the action. Although not historically accurate, they didn't stray too far away, so I was happy about that.
Most of it was shot in blue screen & green screen, and I believe there was only one day shot on location. Considering this, I think they did a really good job of the movie. Apple fans- they processed all this stuff with Macs, with extensive use of Quicktime. Oh, and some Linux.