About the Adapter thingy of Friday: Matooo added support to the Gtk.ComboBox and the Gtk.ComboBoxEntry and fixed some annoyances. He also updated the demo so that it uses a multi-column Gtk.ComboBox, Gtk.ComboBoxEntry and a Gtk.TreeView.
The proof of concept is still an experiment so don’t count on anything becoming stable. Mike Kestner (one of the gtk-sharp developers) commented on the experiment here.
If you want to join experimenting, just ask me for a subversion account. I already gave Matooo one. So :-) update your checkout frequently.