• by Wayne Friedman , January 14, 2010

No matter what happens after 11:30 p.m. in a couple of weeks, NBC has determined what it's doing at 10 p.m., once the Vancouver Olympics runs its course after the closing ceremony on February 28th.

In place of the struggling "Jay Leno Show," NBC has said it will be moving the new Jerry Seinfeld reality show "The Marriage Ref" to a 10 p.m. time period on Thursdays, starting March 4. NBC previously announced that midseason drama "Parenthood" will now become the 10 p.m. show on Tuesdays starting March 2.

The network will also move its long-running drama "Law & Order" to a familiar 10 p.m. time period on Mondays. Starting March 1, the series has a two-hour edition that night, beginning at 9 p.m. It will settle into its regular 10 p.m. slot March 8.

The "L&O" companion series "Law & Order SVU" will also go back to a 10 p.m. time period, now on Wednesdays, starting March 3.

Also as expected, NBC will have its "Dateline NBC" news magazine running on Fridays at 10, starting March 5.

Many of these changes were anticipated. On Sunday, Jeff Gaspin, chairman of NBC Universal Television Entertainment, said he expected at least two scripted shows, one reality and one "Dateline" would fill the soon-to-be vacated "Leno" spot.

Concerning late night, People reported on Thursday that Conan O'Brien will host his last "Tonight Show" on Jan. 22. In a highly followed public letter earlier in the week, O'Brien, addressing "people of earth," said he would not go ahead with NBC's plan to host "The Tonight Show" should it move to a 12:05 a.m. start time.

Other midseason NBC programming news: Medical drama "Trauma" returns for a spell with fresh episodes at 9 p.m., starting on March 8. "Who Do You Think You Are?", a documentary magazine series focusing on celebrities, starts on Friday, March 5 at 8 p.m. "Friday Night Lights" then returns April 30 in the same time period. Game show "Minute to Win It" gets the 8 p.m. Sunday night time slot, beginning March 14.