As commenter Tom suggested, it turns out this was just a bad listings release. NBC has updated it to remove Community and Whitney whose premieres are still TBD.
Whitney and Community were originally scheduled to debut on October 19. Then NBC said it was holding back on that because it said it wanted to focus its promotion on its new Monday-Wednesday shows. This led some folks to wonder if NBC wasn't just holding the sitcoms back to ultimately pinch hit for struggling performers like Animal Practice.
A repeat of Grimm is now scheduled on October 19 at 8pm, and the burn off of the Mockingbird Lane pilot is scheduled for October 26. But the latest NBC schedule update has episodes of Whitney & Community airing on Friday, November 2.
That's still a few weeks away, and who knows how many times it will change before then but here's are the current listing blurbs for Friday, November 2:
11/02/2012 (08:00PM - 08:30PM) (Friday) :
11/02/2012 (08:30PM - 09:00PM) (Friday) :
"THE HOUR OF DEATH"
11/02/2012 (09:00PM - 10:00PM) (Friday) : A SERIAL KILLER DESCENDS ON PORTLAND AND THE WESEN COMMUNITY IS IN GRAVE DANGER -- When a brutal vigilante homicide is made public, it sends Portland’s Wesen community into a frenzy. As Nick (David Giuntoli) investigates further, he discovers a pattern similar to that of a particularly brutal line of past Grimms. Is there another Grimm in town, or is Nick dealing with a sadistic copycat? Meanwhile, Captain Renard (Sasha Roiz) takes it upon himself to offer Juliette (Bitsie Tulloch) comfort in handling her ongoing dilemma with Nick. Russell Hornsby, Silas Weir Mitchell and Reggie Lee.