<cracks knuckles>
Counter-Strike + PPC = no no.
It's not the power or the machine spec that's the problem here (although they are major factors) - it's also the input method and storage. Quake just about works with a stylus. Counter-Strike requires faster reactions and a few more keys, plus a high-res (800x600 at least) to play seriously... anything different and the game you're making isn't CS - it just shares a theme.
What is Counter-Strike,
really? Most people think it's the theme and the FPS bit. They're wrong - it's the combination of those and many many other elements that have taken something like 12 revisions over 3 years to perfect, and it's still being refined, even this second people at Valve, in Seattle, are working to improve the mechanics of it all so that literally millions of people across the world can enjoy it even more.
I'll stop my rant here.
And maybe I should point out now that I am one of the co-authors of Counter-Strike, in case you hadn't guessed, so I feel quite strongly about this
Of course, CS on a PPC would be cool, but... it just wouldn't be Counter-Strike. I don't see it being even close until PPCs have matured a lot - and even then, I can't see it working out. FPS's on PPCs generally don't work - it's an interface thing. PPC's and PC's are not interchangeable.