If you were expecting to trash around in the Sunwell Plateau this weekend, think again. According to a Daelo post, Blizzard has taken the instance offline for the next couple of days.
While I can understand the Blizzard dev's taking the realm offline here or there, and taking down an instance for an extended period of time during the week, it does strike me as odd that they would choose to remove access during the weekend – a prime playing time for a lot of folks. And I know that I and many of my friends only raid weeknights, so we have ample opportunity to test out the content on the weekends.
Nonetheless, we can all look forward to reentering the Sunwell on Monday. If this changes, expect to see an update on WoW Insider.