Looks like NBC's experiment with Jay Leno may conclude quicker than anyone expected.

And the big loser when the dust clears might not be Leno, but his Tonight Show replacement Conan O'Brien.

Both TMZ.com and the New York Times are reporting that NBC executives are developing plans to move Leno from his 10 p.m. weeknight broadcasts back to 11:35 p.m. According to the NYT, the plan involves shortening The Jay Leno show to 30 minutes, airing O'Brien's Tonight Show at midnight and Jimmy Fallon's Late Night at 1 p.m.

The news caps a day of dizzying headlines which began with a report on the TV industry blog FTVLive.com that Leno's show would be canceled. NBC executives denied that story in a statement but didn't refute TMZ's reporting later that Leno might move back to his old timeslot.

TMZ said Leno's prime time experiment would end after the Winter Olympics, when NBC moves his show back to the 11:35 p.m. timeslot after taking a hiatus during February for winter Olympics coverage.

The moves sound a bit drastic -- I always expected NBC to cut Leno back a few days in prime time first. And it would cause all kinds of havoc, forcing NBC to move the Tonight Show off 11:35 p.m. for the first time in decades, and requiring the network to find five quality 10 p.m. shows in a serious hurry.

(It also reminds me of a moment in Los Angeles last January when I asked O'Brien if NBC was really giving him the Tonight Show, since they were allowing Leno to do something similar at 10 p.m. Turns out, the Tonight Show died when Leno left; hard to call either surviving show by that name now)

Local and national press has been filled with stories of how Leno, whose show often places last in prime time and has occasionally been outrated by scripted cable shows, is pulling down ratings for local NBC affiliates. Here in Tampa, Leno's show pulled down 10 p.m. ratings for affiliate WFLA by more than 20 percent, which may have cost the station its top ratings in the 11 p.m. newscast.

The Daily Beast noted NBC will make face a national TV critics convention Sunday and an upcoming meeting of its affiliates board soon. That may be why all this speculation is breaking now. 

The story only really rings true to me in one aspect; it completes the total punking of O'Brien by NBC, which started when it let Leno clone the Tonight Show under a different name at 10 p.m.

As always with these TV stories, stay tuned.

Here's a look at a couple of jokes Leno told during his taping tonight about the cancellation rumors: