Was he “acting” or is he bananas? Joaquin Phoenix’s appearance on David Letterman the other night has tongues wagging about what the heck is wrong with the dude! Punk on Letterman for the benefit of brother-in-law Casey Affleck’s documentary on Joaquin? Is Joaquin really quitting acting to become a rapper?! (That HAS to be a punk!) No matter what, it’s worth watching just for the sheer whackiness!