Ah ok, for the future, almost strangeled you.

it might be nice to just have different textures to wrap on the model. Assuming, of course, that this is the way it is done. I am not really sure.
Might be nice is definately and understatement. I'm pretty sure this is how it's done. Also, I'm pretty sure you can break the model up and load a different head and whatnot. I'm not totally sure what Poser is exactly, but your game would have to be modeled in a Maya/3dsmax type program, where you would just create the model and animate it various ways, and then load it into your game, pretty sure anyways. Which then requires you to bring in someone who knows that crap.
In terms of a 3D world, terrain, I have no frickin clue.

The camera stuff seems easy enough, it's just a viewpoint afterall, opengl is going to handle most of this, you just need to worry about culling things outside the view fustrum (viewable volume(thats SO speculation(seriously))).
I think I'm done making an ass out of myself.
edit to your edit:
there's a lot of flexibility with camera views, so that even if *I* don't care for it, it could be an option. Other things are raw speed (it IS native code, after all), and avoiding the use of non-gaming components (Swing/AWT) for gaming
..yep, yep, yep, and another yep for good measure.