Me like this!
I'm not well versed in the whole Tango ideology, but I'm finding a striking similarity between the metacontacts and msn2 set of icons for statuses... would there be a possibility you'd include a version of the WLM buddy but in green?
So far this is my only quip.
EDIT: Forgot something else. Could you add overlay icons to the on the phone/out to lunch statuses? They feel rather empty with that white circle.
Thanks for your effort!