GSM notifies you when the other party has merged your call into a conference. It doesn't provide a notification when they un-merge it, but oh well. For StreamedMedia, I propose adding a new call state flag, Conference_Host: http://people.freedesktop.org/~wjt/telepathy-spec-conference_host/spec/Channel_Interface_Call_State.html#Channel_Call_State_Flags For Call, I think the idea is to add flags to http://telepathy.freedesktop.org/spec/Channel_Type_Call.html#Call_Member_Flags but I will leave that to someone else.
Here is my spec branch.
http://git.collabora.co.uk/?p=telepathy-spec.git;a=commitdiff;h=e56bfd95e691e5465d5121ad580a2ef24bb88c16
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