Harpo Does Something Funny: One of Kevin Smith's only films to allow extensive improvisation, as all the performers were famous for their lengthy ad-libbed scenes from Judd Apatow films.
Playing Against Type: Of a sort; Jason Mewes gained fame by playing the foul-mouthed, aggressive and abrasive Jay (of and Silent Bob fame) in The View Askewniverse. In this movie, his character is still a complete doofus, but he's a lot more pleasant, calm and good-natured.
Production Posse: Two separate production posse's here, both Kevin Smith's (Jason Mewes, Jeff Anderson, producer Scott Mosier, DP Dave Klein) and Judd Apatow's (Elizabeth Banks, Craig Robinson, Gerry Bednob).
Reality Subtext: The production of the titular (hehe) porno reads a lot like the production of Clerks: filming in the workplace after hours, using a hockey stick as a makeshift boom mic pole, etc. The only difference is Clerks was made with the knowledge and permission of Smith's then-employer.
Kevin Smith specifically wrote the role of Miri for Rosario Dawson, but scheduling conflicts prevented her from taking the part.
Early drafts for the film go as far back as the late 90s as a Spiritual Successor to Chasing Amy and would have starred Ben Affleck and Joey Lauren Adams as the titular characters.
George Carlin was to play the owner of the building where the gang first attempt to shoot Star Whores, but was on tour during shooting. He had his fatal heart attack a few months before the film was released.