Maybe the Osbournes could learn a few things from Ashton Kutcher. Unlike MTV's increasingly tiresome first family, the ''Punk'd'' producer is walking away from his successful celebrity-pranking series for the network after just two seasons -- but not because MTV wasn't willing to cough up more dough. ''I think you keep it new or it's through,'' Kutcher, 25, explained at a press junket for his new film, ''The Butterfly Effect'' (opens Jan. 23). ''I felt like we'd done it, we'd seen it, we'd done a bunch of different people, and if it wasn't going to be new, I didn't want to do it. And I get bored really, really quickly.''
Kutcher also acknowledged that he isn't the only one with a short attention span. ''You have to remember that the MTV audience is extremely fickle,'' he said. ''And then they find the next cool thing that exists. So if you can't change it and make it the new hot thing, don't do it, because you're going to fall off the cliff.''
In addition to ''My New Best Friend,'' a remake of a UK hidden-camera show in which contestants must try to convince friends and family that an improv actor is, yup, their new best friend, Kutcher is developing another ''hybrid, really pleasant'' show for MTV called ''Snafu.'' He's also at work an as-yet-unnamed pilot for Fox with ''Butterfly Effect'' writer/directors Eric Bress and J. Mackye Gruber.
None of those projects are likely to distract the media from Kutcher's May/December relationship with ''Charlie's Angels: Full Throttle'' star Demi Moore. But the ''That '70s Show'' actor doesn't blame his girlfriend for his tabloid It-boy status. ''I did the cover of Rolling Stone, hosted 'Saturday Night Live' and 'Punk'd' really started getting mass media attention before I met Demi, and then when we started spending more time together that got even more attention,'' he says. ''Do I rejoice in the fact I can't leave my house without getting followed? No. I don't think anyone would like that. It's a little creepy. But I wouldn't have it any other way. Because if it went away, I wouldn't be in the position I'm in right now.''
Still, he says he won't be courting more exposure by costarring with Moore in a project of their very own. ''We work together on life every day, and that's the biggest job that anybody has,'' he says. Ben and J. Lo, are you listening?