If you do Diablo style characters that are sprite based and prerendered then its great. Poser can be used to render off all the sprite animations. Kind of a poor mans character studio. Plus there are tons of stuff out there so you can do super hero or Tolkien style games without making a lot of your own props. As was said above Poser models are way too high count for real time rendering. The poly count on most game characters are pretty low.