Tomorrow in prime time, NBC presents a giant anniversary special devoted to Saturday Night Live. But tonight, in the regular SNL Saturday night time slot, NBC repeats, in its entirety, the original series pilot, from October 1975. George Carlin is the host, and the musical guests are Billy Preston and Janis Ian. For my column about why I owe my career as a TV critic to Saturday Night Live, see Bianculli’s Blog.