For the PvPers:
" we’re introducing a new PVP brawl with the Eternity’s End update as our take on what solo queue in World of Warcraft could look like. It’s called Solo Shuffle, and we want players to give us feedback and see if it’s a feature we can permanently add. The idea is that we take 6 players, throw them in a pool, and have them fight in 3v3 arena matches in every possible combination you could form among those 6 players. The one with the best rating at the end essentially wins."
Source: Gamerbraves interview