I quite like eye candy, but then again, it's my job to be creative and take an interest in things like that! Although I do agree with addabox in the sence that eye candy must be useful and not just there for the sake of it.
Far from it. I used to work for a software development company and we would never release full versions for public Beta testing. Core functionality would go out, but any new developments, or so called secret features would be tested in-house. Public Betas are only really needed to test robustness on a large scale. It wouldn't be the first time that Apple have introduced a few new features on launch.
I agree with the above and also add the folowing:Piles - New way of organising groups of filesMulti Touch - Ready for a new breed of touch displays later in the yearVirtualization - Install and run Windows apps in OS X
I really hope the built in mapping and GPS functionality do happen.
Vista IS a performance bottleneck! Also, not to diss your design or ideas, but take a good look at Apple design principles. Apple are big on standards, even in new concepts and although I like your cube idea, I would see Apple implementing something more along the lines of the flip / ripple effects as found in Dashboard and on the iPhone.