Hmm. If I understand it right, Genie / Vala serves as a vaguely C++ / Java like front end on top of C, that allows you to manipulate Gnome GObjects as if they were actual objects, rather than manually-managed C structs.
The thing is, Mer has pretty much gone the Qt route, so it uses real C++ objects. I'm not sure why you would need Genie at all?