I installed Gentoo Linux over the weekend.
I seem to do this about once a year. I will use Linux for a while and then shelve it, then usually delete the partition to install something else I want to play with at the time - the latest Vista CTP at the moment.
I really *want* to like Linux, but there are some apps I really can't do without, so usually go back to Windows. One of them of course is Visual Studio 2005.
I thought I'd try Mono Develop again. I haven't used MonoDevelop since about 0.5 build. I must say it has improved markedly since then. Now at 0.91 it is getting polished.
The only problem I have with Mono is that while most of the libraries are cross compatible with the Windows equivalent, you can't build cross platform WinForms apps. This is to do with problems the getting GTK# to work under Windows apparently. This is a shame really. It would be fantastic if you could create an app in Windows or Linux and have it work on the other.
With that disappointment out of the way, it must be said that MonoDevelop is one of the better - if not the best - IDE's for Linux. If you're developing for Linux, you could do a whole lot worse than MonoDevelop and C#.