   Separation of work between artist and dev
  My roommate and I are planning to make a game.  I am a programmer with a decent background in math and physics.  She is an artist and can do things like high/low poly modeling, texturing, UV mapping, basic animation and rigging.  I am planning to use XNA Game Studio 2.0, which claims to allow for healthy separation between art and programming.  Where exactly is this separation?  I understand the concept of the Content Pipeline where I can import pre-made models, textures, audio, etc.  But who is responsible for things like lighting or bump mapping?  Are those effects that can be defined as part of a model before the model is imported?  What if I want to animate a character?  The character would move in response to events in the game.  Who would be responsible for defining these movements and mapping them to game events?  What about particle effects?Thanks ..   
  The idea behind separating art and programming is very similar to how you would create an interface separate from an implementation [to put the whole thing in programming lingo].  You would do your programming using a theoretical generic bit of art, like a arbitrary texture, an arbitrary bit of static geometry, a player with a set lists of states or actions [walk, run, attack, look at,etc], and do all your coding with these.  The artists job is going to be to make the actual assets, and define what sequence of moments the command to 'walk' corresponds to for a given character, specify various anchor points, and render out the geometry.  Stuff like navigation graphs, bounding geometry, and all that stuff will be generated procedurally in most instances upon load time [or injected into the asset file itself, if you're willing to use your own file formats]Effectively, you're going to be shooting for 'data driven design'.   