As of today, we associated KDE with customization, with the ability to customise every single thing on your computer.
This is a good idea in general but it as it's weakeness. For me, who is a general user running Suse Linux with KDE 3.5.5, I want to have something pretty, clean, efficient and easy to use. We have a website kde-look.org to find your theme and skins except that most of the theme/skin are either not efficient nor professionnal, or you have a post about a screenshot someone made and a description of how he would like to have a specific theme created for him. Kde-look.org lost it's usefulness to user like me and others.
My thought on that is that while we have to keep this customization feature within KDE, we need to have a solid, clean and efficient theme so that right off the box, KDE can offer the eye candy, the appeal, of Vista and OS X. One good thing to start with would be to take an example from MSN Live! Messenger which has included the titlebar within the program. This brings a nicer look where you see the program as a whole and not a program runned inside a box (Title Bar looks like a box to me... )