Confused about effects physics vs. gameplay physics? [H] has asked ATI, NVIDIA, Havok, and Ageia about the two. They received in-depth responses providing great detail regarding effects and gameplay physics, what they mean for gameplay, and current hardware physics abilities.
"After digesting all of these great replies from the players in the physics market, here is what we come up with. There are big definitional differences between effects physics and gameplay physics as you might have expected, but much of the forum banter you have seen people prop up as fact, is just simply bad information at best, and lies at worst."