In many ways Xenos will still be a superior graphics processor to R580, IMO, especially for a closed box environment. Still, delaying into next year wouldn't have had significant impacts unless they delay it long enough to move to a smaller process; if the timings were such that 90nm was still to be used then I doubt the internals would be very different, all it would have achieved is loosing out on sales while no other next gen systems were around.