CBS Entertainment President Nina Tassler said NBC’s decision to program the now-ailing The Jay Leno Show in primetime was “misguided” and though it allowed her network’s 10 p.m. dramas to generate more ad revenue, “it had a negative impact on the business.” She had more harsh words for NBC, which has yet to announce definitively what will happen to the future of Leno or Conan O’Brien.

“Ultimately there is no substitute for developing great programming, working with great talent and getting your programs on the air,” argued Tassler, who spoke to the nation’s TV critics today in Pasadena, CA. “Our creative community was somewhat bruised by (Leno). As it was taking place, a lot of people were put out of work. A lot of people saw this as having a pretty negative impact on our business right now. I think it was misguided and our business is thriving right now. We are enjoying success with new hit shows, as is ABC, as is Fox. Leno was an experiment that obviously did not work.”

In other news, Tassler said Charlie Sheen’s ongoing legal woes shouldn’t affect production of the network’s top-rated comedy Two and a Half Men. Sheen was arrested Christmas Day on suspicion of felony menacing, domestic violence and other charges. He will return to Colorado to face the charges next month. “We’re being very sensitive to the fact that it’s a very personal and very private matter for Charlie,” she said. “It has no impact on the network. His show is proceeding along with its regular production schedule and has had no impact. Right now, it’s business as usual.”

Tassler didn’t beat around the bush when she answered a question about whether the organ transplant drama Three Rivers has been officially cancelled. “Unfortunately we’ve all known each other long enough that when something is on hiatus, its code for something else.” But she acknowledged the network still has plenty of new series to program, including 18 more episodes of  the actioner Flashpoint and 13 episodes of the new drama The Bridge, an Aaron Douglas starrer about a cop-cum-union rep. “We had a terrific fall launch,” she said. “A lot of our shows are working so we had more content than we had real estate.”

More from the winter press tour:

Big Bang scoop: romance for Penny and Sheldon?

ABC has ordered eight episodes of the new drama Scoundrels for its 2010 summer lineup. The series, which is based on a show from New Zealand, is about a family of small-time criminals that is uprooted when the dad is thrown into prison for an extended period of time. The mother then tries to encourage her children to go straight. The drama, written and exec produced by Richard Levine and Lyn Greene, has yet to be cast.

A Fox insider confirmed that the network has always been interested in Conan O’Brien for its (struggling) late-night lineup – says “he’s great!” – but cautioned that the comedian is still under contract with NBC. Still, that hasn’t stopped media outlets from posting reports that the competition may be gearing up to steal the 46-year-old host of The Tonight Show should he balk at a plan to move Jay Leno back to 11:30 p.m. Right now, NBC remains committed to O’Brien as its Tonight Show host; it released a statement saying, “He is a valued part of our late-night lineup, as he has been for more than 16 years and is one of the most respected entertainers in television.” But questions are sure to arise over whether O’Brien would settle for a midnight berth behind his predecessor, should NBC follow through with its already controversial plan. For now, nothing’s set in stone so no one’s talking — but the network could be waiting to make an official announcement on Sunday, when it meets with the nation’s TV critics in Pasadena, Calif.

On the one hand, having the (once popular) Leno as a lead-in could give O’Brien the ratings boost he needs. The comedian is routinely trounced by David Letterman — season-to-date, The Late Show is averaging 4.2 million while The Tonight Show trails at a mere 2.53 million. O’Brien’s Tonight Show is down 50 percent versus a year ago when Leno was pulling in an average 5.02 million while wrapping up his final year as the King of Late Night. At the same time, O’Brien probably wouldn’t have signed a multi-million deal with The Tonight Show almost six years ago if it meant airing at midnight — or else he might have bolted to the competition once his contract on Late Night expired. Ever the class act, O’Brien didn’t refer to the big shakeup in his Jan. 7 monologue (Leno, meanwhile, quipped, “I understand Fox is beautiful this time of year”). But O’Brien’s not above a little self-loathing. In his opening night monologue last summer, O’Brien gave a humble shout-out to the ”man who hosted this show for 17 years [and] took very good care of this franchise…Mr. Jay Leno,” before deadpanning, ”and he’s gonna be coming back on the air, I think, in two days — three days, maybe, tops.”

Stay tuned.

For more on the late night news:

Jay Leno takes a swipe at Letterman: latenight chaos continues, Conan and Kimmel weigh in

Craig Ferguson on the Jay Leno Move

Jay Leno jokes about cancellation rumors