That graph is flat out wrong.
s the list of all of the titles currently using Havok. If you do a simple search you'll see that there are ~124 PC titles in there. All in all there's over 200.
Note here that I'm not saying in any way that Havok is better than PhysX, because clearly it isn't. Instead of saying "Havok" I could have said "physics run on the CPU".
If you want GPU only physics, why even have this discussion, because is there any game that isn't using PhysX for gpu accellerated physX?
I'm just saying that "GPU assisted physics" is a feature nvidia currently are touting as a major advantage of their cards and I'm just pointing out that that argument bares no weight at all. It's currently only being used for things that could be done on a CPU 10 years ago, but now suddenly require a gpu to run. Then they limit the performance of PhysX on CPUs to make their cards look better. See where I am going? Nvidia being the only one having PhysX is only hurting the market, not advancing it.
I would very much like to see future titles make use of the PhysX effects shown in the plethora of different demos out there, but with only one camp having access to those features I don't see it happening.