Rumor is going around that Blizzcon attendees have gotten emails announcing Wrath of the Lich King beta rolling in 3 weeks. Bornakk (Blizzard Forum Representative) pointed out these emails are fake.  These emails have not been sent by Blizzard. ( Source)

Bornakk:  The information here is still active and hasn’t changed:
https://forums.worldofwarcraft.com/thread.html?topicId=2215494466&sid=1

Please be cautious (as always) anytime you are asked to provide account details.

Fansites registered in the Blizzard Fansites Program might probably be among the first to know if Beta is nearing.  No updates given yet, nor an ETA.