Is Joaquin Phoenix Just Another Actor in Meltdown, or is This a Hoax?

Did you catch the now-infamous Joaquin Phoenix interview on Letterman? If not, here's the interview:

YouTube - Joaquin Phoenix Odd Letterman appearance - 02/11/2009

Many are wondering if the whole thing isn't an act, since brother-in-law Casey Affleck is following Phoenix and shooting everything for a documentary (supposedly about his rap career).

So what do you think?

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"Even though I'm no more than a monster - don't I, too, have the right to live?" -- Oldboy (2003)