So in the updated patch notes, under the PvP heading, there are a few changes.
Arena matches now have a 25 minute time limit (was 45 minutes).
Rated Battlegrounds now share the same spell restrictions as Arenas.
This is gonna be horrible. Why limit the spells usable in RBG. This pretty much eliminates some major spells that some classes rely on. I am no expert (I have one of every class except hunter, warrior, monk) but I see this as a huge inconvenience. Most notably, lay on hands, rebirth (pretty much the game changing spells if used right). If there are others, please let me know, but I see this having a adverse affect.
Why they thought this change was necessary is beyond me. I think its a step in the wrong direction.
PS: IMO the time limit reduction was needed, I had way too many matches hit that point and it felt like a waste. But i think 25 minutes is too short.