I think too much end users reviewing KDE 4.0 already, they never want to understand the reason why those new technologies are implemented (yeah, why the heck they should care, they are only users used to proprietary software). To re-emphazise: KDE 4.0.x was intended for developers so that they can start porting their applications to the new library.

Why they ripped File Management function in Konqueror? Because it was a mess in term of code and nobody did a real maintenance. Someone came up with a new File Manager, and it is quite good, why don't just maintain and improve the new one?. And for your information, Konqueror now also uses Dolphin part to do file management, so the file management part is back, with the fresh code, and the library is shared between two applications, is that good?

And also, why people always comparing KDE with Vista, even the Oxygen widget theme is far from Vista-ish. About the black theme, you can change it to any color you want, the default doesn't meant you have to use it. Do you know that default GNOME theme is an utter crap, but distro usually change the default to make it more pleasant to your eyes. And I'm always wondering why it is always a sin when something resembles Windows but it is ok if it clones Mac OS X?

Also, Compiz is good as compositing manager, but it's window management feature really _sucks_, not to mention the configuration is a real PITA. And it would be really hard to make Compiz work well with KDE (in terms of integration). Even GNOME is adding compositing feature to Metacity (and also XFCE already got compositing feature, so I wonder who will use Compiz in the future, fvwm95 users, huh?).