No word on the release date yet, but here's a blurb from GuitarSquid.com:
The documentary has been in the works for a while now. Titled White Knuckles and Blue Moods, its significance changed with Moore's recent passing. A 2011 release was originally planned and still seems to be the target, but additional production is reportedly underway in an effort to include details about his passing and further perspective about his life and impact as a guitar player.

Trailer: