We are getting numerous tips that servers are crashing. Blue poster Aredek says it is a realm connectivity problem and that their technicians are looking into it. Currently, there is no time for when they will have an update.
We will keep you posted as usual.
Update 6:45pm: The realms are expected to be back up by 7:30pm EST.
Update 6:27pm: The Realm Status forum has posted the realms affected, which we have listed after the break.
[Thanks to all who sent this in!]