Apple has trouble with video cards?

With the last AGP G5s, we had retrieved something rare on a Mac, having powerful and almost on the edge video cards.
The Geforce 6800 Ultra and Radeon X800/X850, though expensive, offered top of the notch performances.
We'd hoped that PCI Express would bring us even more in this area, yet this is not the case.
Apple once again managed to disappoint us in their graphical offer. The Geforce 6600 LE and 6600 are simply outpaced, ageing cards.
This could have been dealt with if BTO would have offered more performant cards, yet the 7800 GT still to be seen on some documents ) has no commercial existence. And anyway, why not offer a wider selection from the 7800 GTX, even more powerful, to a Geforce 6800 Ultra as mid range card ?
Of course, there is the Quadro FX 4500, yet its costs is prohitive, and buying it only for gaming purposes would be a non-sense. Why not then buy a PC for hardcore gamers instead ?
To sum up, while the G5 moves forward, non professional video goes backwards. It's a frustration for customers who'd fancy a game from time to time, and that will be even more when we'll swith to MacIntel. Potential switchers will have much more solid comparison grounds, and such a drawback will cost much to Apple.
It might also be the only way Apple found to prevent Mac OS X X86 be installed on PCs: only supporting graphical cards no one will accept, save for some convinced MacUsers.
PS: it's in our memory the first time ATI won't offer a model in a G5 line. Is the fact the X1000 is late responsible for this?
PS2: while waiting for the 7800, you may still d/l its manual here:
http://manuals.info.apple.com/en/NVIDIA_GeForce_7800GT_Graphics.pdf