Looks like, other that the usual updated character modeling and such, this one will have destructable content in the buildings and surroundings.
Check out the trailer: http://ve3d.ign.com/videos/15586/Xbox-360/Battlefield-Bad-Company (http://ve3d.ign.com/videos/15586/Xbox-360/Battlefield-Bad-Company)
Looks interesting, might be something to pickup. It has a lot more destruction of models.