I thought that the movie caught two aspects of the book well: The fascist ideology and the bugs. The bugs in the film were awesome. (Well, the soldiers were, anyway. Perhaps the fireball-farting artillery shouldn't be included.)
I'd go for a Starship Troopers game true to the book. The Avalon Hill version was pretty damned good, considering the pains one had to go through to simulate FOW. With an improved FOW system like CMx2 is supposed to have, it'd stand a real chance.
Other than that, I'd have to vote for a Hammer's Slammers / Traveler-type scheme. Yeah, it's "shades of WW2" but what isn't? ModWar is "shades of WW2" but people enjoy playing it as a change of pace, don't they? Besides, the mercenary setting of Slammers/Traveler makes for lots of potentially different TOEs.
Just stay away from 'Droid Wars, OK?