Showtime has opted not to renew the Diablo Cody–created, Toni Collette–starring United States of Tara for a fourth season. Bummer. It has, however, picked up Edie Falco's Nurse Jackie. Both shows have been award winners for the network, but Jackie has double the ratings (around 750,000 versus Tara's 300,000). Showtime's stable of screwed up women is now short a mom with multiple personality disorders.