My good buddy jAkUp over at nV News has managed to get an interview with Tim Sweeney at E3 and has posted the transcript in the forums for your viewing pleasure. Jacob does an excellent job of touching base on all the hot topics as of late including DX10 implementation and hardware physics acceleration. Without question, one of the most interesting responses would be Sweeney's take on Ageia's hardware implementation in Ghost Recon Advanced Warfighter. Come to your own conclusion on the subject by checking out our review of the BFG Tech PhysX PPU.
Sweeney- For the record, acceleration hardware is supposed to accelerate your framerate, not decrease it! [laughs] That seems like its just a messy tradeoff that they made there. You certainly want your physics hardware to improve your framerate. That means that the physics hardware might in some cases be able to update more objects so you can actually render another frame, so you need to have some sort of rendering LOD scheme for that to manage the object counts, and obviously you don't want to take this ultra fast physics card and plug it into a machine with a crummy video card. You really want to have a great video card to match up with your physics hardware and also a decent CPU to have your system in balance to really be able to take advantage of the full thing.