I've never really got the fuss about Duke Nukem. Aside from the release cycle of course, but since the original games simply aren't 'aimed at me' I've never found it necessary to sit hard on my hands whilst waiting for this one.
It would be unwise to get your hopes up based on the release of a teaser trailer of course. They've released more substantial trailers at least twice before now...
edit: If they're keen to recuperate their development cost, they really should consider releasing a 'making of' for the game, should it get released. It'd probably need to be edited down from a War & Peace number of pages...