Three years ago me and a friend started work a new mono project and tried to use MonoDevelop for it. However - this was an impossible mission - we got ridden with all kinds of bugs and crashes and in the end I said - go to hell MonoDevelop - I'll use my tried and true Emacs.
To tell you the truth with no features other than formatting and font locking Emacs turned out to be 10 times more productive environment for me. My friend somehow endured using MonoDevelop for the whole run of the project, but afterwards he said he was done with Linux for good if it offered such low quality dev tools.
Times were different back then, I've been following mono's development and monodevelop's as well - they seem to be turning out quite well. I think that the actual cause of your problem - not finding anything - lies in the fact that most Linux devs openly shun Mono as a development platform because of it's Microsoft roots. This is sad - because it's a solid alternative of Java - especially at the desktop applications front(GTK# is seriously cool).
Banshee seems to be using MonoDevelop. Probably most of the prominent mono projects with a GUI use it as well to some extent.