Alyona Kolomiitseva said:
Guys, we're experiencing some issues. We have already found the source, but fixing it will take some time.
I will update you with new information as soon as I get any. Thank you for understanding. 
The three biggest issues with the down time:
1) Daily log in - depending on how long it takes you to fix, many players will miss out and will have to start over at day 1. Highly unfair when you trapped us out of the game.
2) Tournaments - pretty sure the beacon tournament with unique reward ends tonight and with nobody able to log in, that is an easy win for whoever was in lead when servers went down. Since downtime was not announced, this is a highly unfair advantage.
3) Troops trapped in open - Since server went down with no warning, people were playing the game when it crashed. Raids in progress, bgs being done, etc. That's a lot of troops that we cannot log in to cata. When server comes back up, you'd better believe opportunists will be out looking for troops caught in the open for easy points.
What will Plarium do to make right with the players?