Agreed on the desktop. Damn this is the ugliest desktop MS has put out in some time, relative to modern design I think it's worse than the garish Luna (but that could at least be easily mitigated with a new Style XP skin or when Royale came out). It's just so...lazy. Just flattening some elements while leaving Win7's faux-3d icons everywhere, getting rid of the transparency (which really hurts when you have rotating wallpapers and your border colours to match - hope you like your windows suddenly become brown and hot pink when a new pic appears!), and that's about it. So much more they could have done to make it look professional if they were so dead-set on Aero suddenly being considered passe'.
A lot of people... I mean, a lot of people hated Aero. Flip back through the Coffeehouse to 2006 or so, you'll see what I mean. People thought the transparent borders were extremely distracting and made it harder to read what was on the title bar. And in general, people thought it was "too colourful" and drew too much attention to itself instead of keeping your attention on the apps. We can agree with that or not, but it's not like Aero was ever really thought of as the gold standard of user interfaces.
Windows 8 definitely feels "unfinished" though.... like they just didn't have time to settle on a new coherent design for the desktop. For example, you can still find the Vista-era animations in the change permissions progress dialog. The Speech Tutorial still has a Vista-era close button as well.
BTW, If you don't like the automatic colour changes in the UI chrome when your desktop background changes, turn it off by setting a specific colour. You have all the same flexibility as Windows 7 here, with the exception of the translucent glass effect of Vista and 7. You didn't have that effect in Windows XP so you should be able to live without it in Windows 8.