Journalists often use the word "sexy" in reference to stories that are just about guaranteed to grab mass market attention, regardless of content. Conversely, the arguably more important issues that never get the attention they deserve get lumped under the term "unsexy".
For instance, City Council meetings are not sexy. Charities are not sexy. Scandals and car chases are sexy. Obviously, any story that's even remotely related to sex is sexy.
In politics, gun control and money issues will always be sexy. Election reform and environmental issues, on the other hand, will be perennially doomed to languish below the fold.
Some media networks (*ahem*Fox*coughcough*) have become notorious for jamming their news-hours full of sexiness and pandering in place of "real news". Other outlets, like NPR and the BBC, have built their reputations on coverage of more "boring", unsexy news stories. Of course, that's not to say that one is worse than the other... every poll ever conducted has pointed out that the public happens to like sexy stories a lot more than hard news, and would rather be entertained than enlightened.
(Also note that this same phenomenon has also been known to occur on E2. It's often been lamented that nodes about sex, drugs & rock 'n' roll garner instant attention, while uninteresting but factual nodes gather votes like a rolling stone gathers moss. *shrug* I suppose that's life.)
(Update, January '05: randombit also reminded me that "sexy" is sometimes used in an ironical sense, especially among geek culture, to refer to anything particularly exciting or significant, i.e. "these new images from Cassini are pretty sexy.")