Trailer Time: the insane "documentary" I'm Still Here, featuring Joaquin Phoenix

I haven't been able to figure out whether Casey Affleck's documentary on Joaquin Phoenix's crazy sabbatical from acting is real or not. I'm starting to think that they're trying to pull an Exit From the Gift Shop on us, and that it isn't all that it appears to be. Whatever the case, I'm definitely intrigued by the trailer, which is doing a good job keeping its reality(or lack thereof) hidden. 

I'm Still Here will debut in just a few weeks on September 10th, 2010. Check out the trailer and tell us what you think. Is it real or Memorex?