Someone in one of these threads suggested repeatedly entering your user/pass. I thought it was dumb but it actually worked after a few attempts, just spam login requests. I thought the servers had been down all day because every time I tried to login every hour or so (just once) it didn't work and it seems a bunch of other people are having problems logging in, so give it a try. (This post is for people who have been previously playing but today are not able to, not new players/first time logins who maybe have errors with their realmlist etc)