I was going to ask that question, too. Sticks in my mind for some reason that Scientology is anti-gay.
I can't recall knowing about rumore about Travolta, either, but if the accusations are true, it's interesting to consider the Scientology connection.
I've heard the rumors about both for years, and always thought it an odd coincidence that they're also the two most famous faces of Scientology, and both (potentially) closeted.
I'm not sure what Scientology's stand is on sexual orientation, but you can certainly think of other reasons why Cruise and Travolta would not want to come out. Either, of course, has all the money he'll ever need (and I don't recall seeing Travolta in anything for a while, so maybe he's decided the same), but Cruise is obviously still very interested in maintaining and building his career. And his particular star image is one that still, unfortunately, risks being damaged if he comes out. Thanks to all the other stars who've come out already, I think we're in transition on this, but we're not quite there yet for a star of Cruise's type.