Let's see... 1) Slow UI. Doesn't always show the latest thing I've typed unless I leave the chat and come back to it. 2) Constantly nags me that I am muted.

Let's see... 1) Slow UI. Doesn't always show the latest thing I've typed unless I leave the chat and come back to it. 2) Constantly nags me that I am muted. Close the window and it pops up another one. 3) Notifies me of completely irrelevant things like a person was added to a meeting as if it was a chat message. 4) Meetings and calling seem to rely on some kind of peer to peer system that can break horribly with out anyway to diagnose the issue (e.g. works differently depending on how you access a meeting or call).