Despite the issues associated with the extending of today's maintenance, all US realms are back up and running. We don't have reports of any stability issues, so everything appears good.
Patch 3.0.8 is not out on the live servers, however you can access it on the Public Test Realm (PTR). Today also marks the start of Arena Season 5, so expect a lot of PvP to be going on tonight.
There's also the Winterveil celebration going underway. Today is a great time to get some of those achievements knocked out before the holidays kick in next week.
See you in Azeroth!