> The fit and finish of linux desktops, especially KDE, are nowhere near as good as the Mac
I beg to differ, but only with the "especially KDE" part. KDE is a different beast than most other modern desktop environments, in that it does not try to mimic OS X style in any way.
KDE was started way back when with a goal of replicating a Windows-like UI, with a Start-menu like launcher and a Start-bar like task bar with applets.
It may not be to your tastes, but the fit and finish of KDE3, 4 and now 5 is excellent. Integrated application sets (K[Anything]) with integration into a centralized control/config panel for shortcuts, MIME type handling, ...
The only problem with this is that other popular applications do not bind this tightly to KDE (understandable from application developers - KDE is not the only game in town).
Previously, GTK applications in particular acted and looked like they were from '93 when run outside of GTK-centric desktop environments (XFCE, Gnome). However, Qt has developed a GTK2 and 3 engine that uses Qt and Qt themes under the hood, largely solving that problem when properly configured (try any stable OpenSuse release, for instance).
