Recently a big step towards a unified KDE interface occurred- the oxygen-gtk project. Rather than the imperfect solution of theming where a GTK theme that approximates the KDE Oxygen look is made, this project is an actual GTK engine that will dynamically and perfectly render a KDE interface on a GTK app. Yay! It’s not perfect but it ships in openSUSE 11.4 by default. I can’t say it’s perfect- several apps have a white box in the background of the app where oxygen-gtk appears to be failing to render the Oxygen radial background. Update: The white rectangle is caused by a bug in Cairo + Nvidia’s proprietary driver. If you switch to the Nouveau driver, the white rectangle is gone. There’s also a patch for Cairo if you’d rather keep the Nvidia display driver and can’t wait. Update 2: Cairo’s been updated in openSUSE- Gnome apps are looking great!
If you’re seeing a faint seam along the title bar, make sure your Application Appearance > Colors settings are set to the Oxygen preset.
Firefox 4 looks great in openSUSE 11.4. I’ve got the Oxygen KDE add-on installed from KDE-look. It really looks like a KDE app. No longer distracted!
For those that prefer Google Chrome, take a look at the Oxychrome theme on KDE-look. Follow the instructions and Chrome will look like it belongs in KDE. For what it’s worth, when I unzipped the scrollbars extension, there were no remote exploits or odd code- it’s just CSS. But you can never be sure- so check!