Peter Krause, Seth Meyers

NBC has revealed "Part 1" of its plan for the 2009-10 TV season, and it includes a second season of Parks and Recreation, a half-dozen installments of Saturday Night Live Weekend Update Thursday, and four new dramas.

In addition to renewing Parks and Rec, NBC also officially picked up Heroes for a fourth (albeit likely shortened) season. Previously announced returns include The Office, 30 Rock, Law & Order: SVU, Friday Night Lights, The Biggest Loser and Celebrity Apprentice.

Conspicuously missing from NBC's press release is Medium, despite one trade mag's weekend report that it would be back for a sixth season. NBC sources tell TVGuide.com that in fact a decision on Medium has not yet been finalized, but that the network may announce additional pickups on May 19.

New drama series en route to the Peacock's schedule are as follows (watch video previews here):

Parenthood, based on the 1989 film comedy and starring Peter Krause, Maura Tierney, Dax Shepard, Erika Christensen and Craig T. Nelson (as the family patriarch).

Trauma, from Friday Night Lights producer Peter Berg and revolving around first responder paramedics. The cast includes Derek Luke, Anastasia Griffith (Damages) and Jamey Sheridan (Law & Order: CI).

Mercy, a medical drama told through the eyes of three nurses (played by Michelle Trachtenberg, Jamie Lee Kirchner and Taylor Schilling). The cast also include James Tupper, Diego Klattenhoff (Supernatural) and Guillermo Diaz (Weeds).

Day One, an "event series" slated to air after the 2010 Winter Olympics wrap, and concerning life on earth in the wake of a global catastrophe. The cast includes Adam Campbell, Carly Pope (Popular) and Catherine Dent (The Shield).

On the comedy front, here is the new fare you can expect (watch video previews here):

Community, set at a community college and starring Chevy Chase and Joel McHale (The Soup).

100 Questions, starring Sophie Winkleman (Peep Show) as an unlucky-in-love woman who joins an online dating site.

New reality programming earning a slot on NBC's schedule include Jerry Seinfeld's The Marriage Ref, Breakthrough with Tony Robbins, and Who Do You Think You Are?, in which celebs climb their ancestral trees.

NBC's complete 2009-10 schedule will be announced on May 19.

Also check out: 
Fall TV Scorecard: Which Shows Are Returning? Which Aren't?
Eight Endangered Series We Hope Will Survive
Spring TV Progress Report: The Pros and Cons of 10 New Shows

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