It's the old "I Was Only Trying to Sell Him a Screenplay" defense! So says Robert J. "Joe" Halderman, accused of blackmailing David Letterman. Halderman's attorney, Gerald Shargel, asked a Manhattan judge yesterday to dismiss a charge of attempted first-degree grand larceny against Halderman. When Halderman left a package in Letterman's car, "there was no extortion," Shargel said. "There was a commercial transaction. Nothing more." Letterman went memorably public on his Oct. 1 Late Show when he told the world he'd found the package, with threatening notes, "evidence" of Letterman naughtiness, and threats to go public if DL did not cough up. He and lawyer met with Halderman, who did say he was working on a screenplay on DL's life - and wanted $2 mil. DL even paid him a bogus check and went before a grand jury to crank up charges. Now Halderman says it's all just a big misunderstanding.

Oprah stays mum, wins big

Big, big TV rumor: Oprah Winfrey may move her beloved show from Chi to L.A., and from ABC to her own cable channel, OWN (Oprah Winfrey Network, we're guessing) by 2011, when her current deal ends. The rumor began with blogger Nikki Finke, but folks from Harpo, Oprah's nice big company, say O has "no immediate plans" and will say something "before the end of the year." Problem is, sometimes that means Yes. . . . Who owns the phrase Aha! moment? Oprah, that's who! Mutual of Omaha has withdrawn its suit against O. It wanted to use the words in some ads, but O said no, and now M of O and O are OK.

Everyone is always naked

Latest celebeauty to bare all for animals is Christian Serratos, she of the Twilight films. She appears in the latest PETA campaign. Everyone from Christy Turlington to Alicia Silverstone to Eva Mendes has bared her beyond for the cause of furlessness, vegetarianism, and beast nicety. Eva also pouts aloud to Mail Online that Kate Winslet gets all the roles Eva wants! Not that you'd think of the two in the same head, but OK. Now watch Winslet start grousing that Eva's taking all the sexy billboard undies ads. . . . Who, oh, tell us, who will be on Sports Illustrated's 2010 "Swimsuit Issue," which, as the world knows, isn't soft porn masquerading as legit sports journalism? Rumor says that lucky world athlete will be Brooklyn Decker, 22, wifey of tennis deity Andy Roddick. . . . Oh, look, here's Eva Mendes again. Her annual Calvin Klein traffic-stopper sprawls hugely on a public wall in SoHo now. Sweaty, lingerie'd Eva, fresh from healthful exertion, is foolin' with some dude's boxers. Outcry! Too hot for fall!

Water, that magical elixir

This just in . . . HINT Essence Water is teaming up with Disney for the Dec. 11 rollout of the new animated family epic The Princess and the Frog. HINT is said to have completely transformed the bottle for their Blackberry essence water. So does it taste more like frog or more like princess? Just asking for information. . . .

Hip-hip-hurray for Halle

Halle Berry will receive the Sherry Lansing Leadership Award at The Hollywood Reporter's 18th Annual Women in Entertainment Breakfast. The awards nosh, sponsored by Lifetime, happens Dec. 4 at the Beverly Hills Hotel. Hilary Swank and bad pole-dancer Eva Longoria Parker, two other leaders, will speak. The annual do is part of HR's "Power 100: Women in Entertainment" survey. . . . From the Sublime to the Get-Outta-Here Dept.: Did you see Parker pole-dance on George Lopez's Lopez Tonight debut Monday on TBS? She tried a back-hook spin, but her big, cute heart wasn't in it. George showed her how it's done.

SideShow likes sex tapes

Never, ever have sex with anyone - that person will just go and make a video of it. Former Miss California Carrie Prejean said on Tuesday's Today on NBC that making that dratted old sex tape was "the worst mistake of my life." D'you mean, Carrie, that it was, like, wrong (yay: she has a moral sense), or just that it forced you to drop your big-old lawsuit recently (boo: I din' get paid!)? . . . Jennifer Lopez is suing former husband Ojani Noah for $10 mil and trying to block a vid of him and her him-and-herring in 1997. His docu-dish is titled, cleverly, How I Married Jennifer Lopez: The J.Lo and Ojani Noah Story. No, really. That's what it says here.

Contact "SideShow" at sideshow@phillynews.com. This column contains information from Inquirer wire services.