About the Ars rumor on Mac OS X 10.6
Ars Technica: Mac OS X 10.6 code named Snow Leopard, may be pure Cocoa
It's funny how people are getting all freaked out about this rumour. Some people are saying they should release it for free since Leopard is so unstable. Given my issues with Leopard I can sympathize with that, but 'na gana happen.
Then people are worried about the "pure Cocoa" label. As Jacqui says, all it means is all of Carbon's APIs will finally be available to Cocoa programmers via Objective-C wrappers. It's about time! It doesn't mean Carbon is going away, not unless Apple wants to lose Office, Creative Suite, Quark, Firefox, and more. 'Na gana happen. Pure Cocoa might also mean Apple won't ship any more Carbon apps themselves, ie: they've ported their remaining Carbon apps over to Cocoa. This is quite plausible, it would have been an effort like this that would have helped Apple understand how to best wrap the remaining Carbon-only APIs.
As far as Intel-only goes, it's inevitable! Even if Apple kept PPC support in until 2010, they would get hammered over it, so they might as well do it now and reap the manpower savings sooner. The only PPC machines out there that are even worth using compared to current Intel systems are dual and quad PowerMac G5 towers, and G5 Xserves, and that's a pretty small percentage of the PPC systems out there.
I equate the stability issues with Leopard to Apple's resourcing issues. Remember Apple had to delay Leopard 6 months because they had reassigned developers to the iPhone. Developers good enough to work on OS X and Mac OS X don't grow on trees, there is only so much talent they can get their hands on. I think they're probably quite thin on the resource front right now because they're taking on so many platforms at the same time: Mac OS X, iPhone/iPod Touch, Apple TV. If removing PowerPC support helps free up some talented developers to work on stability issues and other serious bugs, then please do it.