Comment #10 on issue 492 by esteba...(a)gmail.com: Glamour browsers do not
release all subscriptions to announcer objects
http://code.google.com/p/moose-technology/issues/detail?id=492
and well... #testAnnouncerUnregistration seems to be testing the
announcement unsubscription in a series of events (changing selected
entities and general unregistration). I don't know why that test does not
catch our problem. I presume that changing entities does not "fires" the
presentation update mechanism who finalizes in a copy, I really don't know
why :)