To the surprise of few, the critically reviled “The Michael Richards Show” was canceled by NBC on Thursday. Last week it came in at No. 78 on the Nielsen list. The network said that the sitcom, which features the former Cosmo Kramer (of “Seinfeld”) as bumbling private eye Vic Nardozza, will air through Jan. 2. Its timeslot will then be taken over for a largely revamped Tuesday night lineup that is set to include a new series, “Three Sisters,” with “NewsRadio” actress Vicki Lewis and ’60s and ’70s screen star Dyan Cannon (“Bob and Carol and Ted and Alice”). In other TV news, comic Chris Rock has canceled his own HBO series after four years on the air. He says he wants to focus on his movie career.