Starship Troopers 3 (!!!) is in production!!!  Starship Troopers:  Marauder.

It was obvious from the other movies that each movie is simply a single small part of the whole war.  The cartoon series is especially nice in terms of how it adds more detail.  Starship Troopers is interesting in that it takes place in the very near future and doesn't create fantastic new weapons but instead takes a small incremental step forward making it seem far more plausible.