It's a hoax. Everybody has denied it.
I might be interested to see the film. Though I think i'd rather just play a Nirvana record. Far more enjoyable then what Urban said it'd probably be
Although... if this did go through, who should direct it?
I'd want the director to be an artistic original, which I think would be closer to the band's message, then somebody who'd treat it too much like a step-by-step recounting. Quentin Tarantino FTW!