AMD Claims NVIDIA Bribes Game Devs To Use PhysX
 

ATI, graphics business unit of Advanced Micro Devices, accused its arch-rival Nvidia Corp. of making marketing deals with video game designers to promote GPU-accelerated physics effects processing using PhysX application programming interface.

Earlier this year AMD already accused Nvidia of modifying PhysX API in a way to not let it use all available cores on multi-core central processing units (CPUs) when processing physics effects in games. The company claimed that Nvidia did this in order to look performance of GeForce-accelerated physics effects processing higher compared to CPU-accelerated processing. However, later on Nvidia denied any modifications of PhysX API.

http://www.xbitlabs.com/news/multime...ote_PhysX.html

Well ... duh! Of course Nvidia will try to convince game devs to make use of PhysX

what they are stating is just how the world works; those who develop don't necessary control how and what; the marketing/sales/directors decide the tools used and the deals made;

if the devs want to get paid, the company makes a marketing deal with NVIDIA, company gets money to pay the devs, in return the devs use PhysX in their game engine.