The website dubs it as the private joke between comedians. Its "never been told in public" and gives us a glimpse into over 100 comedians. The film opened a few weeks ago in select cities and was discussed in the Sunday NY Times the week prior to its launch. If you look at the cast of characters, if you can even call them a cast, you'll names such as: George Carlin, Drew Carey, Andy Dick, Eddie Izzard, Jackie The Joke Man, Chris Rock, Rita Rudner, and Sarah Silverman.
People who are thankfully missing from the full list are Will Farrell, Owen Wilson, Vince Vaughn and Luke Wilson. While all four have been good in their movies recently, i'm getting tired of the 21st Century version of the Rat Pack. Plus I highly doubt any of those four have ever done stand-up.
Either way, it looks like its worth checking out. Here's the link to the site. Check out the trailer. Good times, lots of laughs.