I always think that the mark of a really good addon is when Blizzard incorporates it into the game, and it looks like this is exactly what's happening with LoseControl. The Blizzard blog with the official 5.1 PTR patch notes had this to say:
Additionally, new strings have been datamined that indicate that these banners will show the type of CC a player is subject to, as well as the effect itself, so, for example, Psychic Scream is a fear effect, and can be removed with Will of the Forsaken or a Tremor Totem, whereas Mortal Coil is a horror and cannot.
As someone who is a big fan of LoseControl, I heartily applaud the introduction of this new UI element by Blizzard. It removes a small layer of difficulty from PvP, and indeed from PvE, by illustrating to players just exactly what's happening to them and allowing them to respond accordingly. In response to the inevitable complaints about catering to the casuals, this doesn't tell you what to do about the CC, only what it is. The player still has to react.
Update: I was able to get onto the PTR and get you this screenshot!
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