Is it a documentary or a mockumentary? Either way, Magnolia Pictures has snagged the world rights to I’m Still Here, the Casey Affleck flick chronicling actor (and brother-in-law) Joaquin Phoenix’s departure from movie-making and ill-fated entry into hip hop music. Magnolia had been among the buyers sniffing around the project once Affleck began screening it for potential suitors. Phoenix had garnered much media attention during his ‘retreat’ from movie-making (which, it seems, was being filmed all along), particularly for his bizarre behavior during an appearance on The Late Show with David Letterman. The film will be released on September 10 – no word on whether it will be accompanied by a soundtrack.