I thought it was okay. The meta nature of the film was very interesting and I thought the murderer(s?)' motive was a nice twist (I'm not going to be the one to spoil either... for the most part). It wasn't all that funny and I thought the deaths were fairly predictable. I loved the bit at the beginning with Anna Paquin and Kristen Bell. THAT was fun.
One question of a spoilery nature: