Screenshots at http://unityisntthatbad.blogspot.com/
Me no guru.
I don't know how something like this happens, or even if what I think is happening is what's happening, but it looks to me like some KDE applications (or at least one KEY KDE application, the Dolphin File Manager, has been set up to be integrated with Unity, instead of integrating with KDE.
Here's Dolphin in Kanotix, a distro based on Debian Squeeze:
The inset red-lined window is a close-up of the upper toolbars, and you can plainly see that there are two of them. You see the same thing when the dolphin window is maximized:
But you only see one tool bar when you open Dolphin in Kubuntu:
The upper toolbar, containing some important functions (File Edit View Go Tools Settings Help) cannot be found. You get the same result when you maximize Dolphin.
At first, I thought this was somebody's horrible design choice. But then it got weird. I happened to try Dolphin in Ubuntu 11.10, with the Unity Interface, after a hard drive install.
In Unity, the unmaximized dolphin does not display the upper toolbar, either, but WHEN YOU MAXIMIZE DOLPHIN...
There it is! This is consistent with Unity, and that "Apple" upper bar feel that someone somewhere apparently loves so well. Here are a couple of screenshots of Nautilus in Unity, to demonstrate hiow that's supposed to work.
I want to emphasize that the Kubuntu screen shots were taken from a live images on a USB device, where ubuntu-desktop had not been installed. Hopefully, Kubuntu is already aware of this problem. My Ubuntu hardrive install was short lived. I'm running Kanotix on my hard drives, so I can't be sure how other KDE applications were affected.