US Servers will come down on Thursday, January 3, 2013, at 7:00 am Pacific* for an update. The expected downtime is one hour. The EU servers will come down on Wednesday, January 3, 2013 at 9:00 pm Pacific. The Japanese Server will down on Wednesday, January 3, 2013 at 1:00 pm Pacific. The expected downtime is one hour.
Update Notes are posted here Game Update Notes.