Here's a breakdown of the actors used:
A mix of live action, “Big Bird sized” monster costumes, and CGI - Wild Things employs the vocal talents of Forest Whitaker, James Gandolfini, Michelle Williams, and Catherine O’Hara, and also featuers Catherine Keener, as Max’s mom on-screen. A heretofore unknown, Max Records (seriously?), was cast as Max, the fictional.
For an update on the movie, including a still from the film and analysis of the script, go here.
I cant tell you how excited I am at this one. I think a large number of us grew up reading and re-reading this book and I cant wait to see how they adapt this to the big screen. Its been a long time coming and as long as it doesn't play out like "The Neverending Story" I will be a very happy person.