Blizzard president Mike Morhaime, explains what was going on in today's regularly scheduled maintence down time, and a one day extension for the affected realms.
This is the post that was on the forums at www.worldofwarcraft.com
Regarding Todays Maintenance
Due to the increase in downtime caused by todays hardware maintenance, we will be giving all players with characters on the realms listed below a one-day time extension. In addition, players on the realms below will also receive a rested experience bonus, whether or not they had left their characters logged out at an Inn.
We realize that this extended downtime is very inconvenient, but it is a necessary step for us to take in our efforts to increase performance and stability on these realms. For the last few weeks, these realms have experienced poor stability during peak times, which resulted in NPCs not spawning, lag, and frequent disconnects. We have determined that a large percentage of realms on the same backend infrastructure were operating at maximum capacity. This overpopulation caused problems with the service that ultimately led to the issues mentioned above.
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