Why did Namco cancel the PowerVR PC versions of Rave Racer, Air Combat 22 & Tekken?

Time to bump this thread - Videos of PC PowerVR Rave Racer surfaces ^__^

http://www.youtube.com/watch?v=onZi_-Xzqyk (starts at 1:30)


also:

https://www.youtube.com/watch?v=aBuGwrWP-s4