It's all good!
I hope they go no further with the "clutter," but I think the Store looks great as it is. Too much austerity and people think they're getting ripped off. "Is that all there is???? I'm outta here!" I think the bleak white backgrounds Apple has used for so long in its ads have worked to put as many people off as they have attracted for that reason. The current version of the Store and the new iPod ads strike a great balance between flash and simplicity.
Oh, and about iTunes for Windows: I wish Apple all the success in the world with this ambitious/necessary endeavour... but the interface looks a bit ugly compared to the Mac version. I hope the Windows community takes to it. The in-window menu headers really look squeezed in.
Yeah, I know Windows users are used to a hodge-podge of interfaces across their platform, many of which we wouldn't tolerate on a Mac OS. Just an observation that we have it better, if only that the brushed metal blends in with our UI.