Senior Game Master Salorius has announced that Blizzard will be restarting all realms at 5:00AM Pacific Standard Time.
The European servers were restarted at 5:00AM Paris Time.
Downtime is supposed to be minimal.
There is no official announcement as to why the realms are being restarted.
What do you think the reasons for the restarts are?
Update: The post was updated to say the restart was to correct some "performance issues".