We're currently aware of issues with finding matches in matchmaking. We've diagnosed the problem and are currently working on a resolution. We'll keep this thread up to date as further information becomes available.
Thank you for your patience.
Update 2:05pm EDT: EU servers are experiencing the worst of the problems right now but, we've got enough back to an available state that queue times should start getting back under control. We'll continue to monitor the issues and work on getting back to full capacity.
Update 2:53pm EDT: We've determined and resolved the cause of the problem. Matchmaking queue times will continue to become better as capacity is restored to normal. Thank you again for your patience.