"The Warhammer 40,000: Dawn of War II multiplayer beta is scheduled to open to everyone on the 28th of January, as reported by GamersDigest in one of their previous articles."
You can get early access however;
"GamersDigest is proud to announce that we have 25 early access beta keys for the Dawn of War II beta, courtesy of THQ."
Update
http://www.gamersdigest.net/342/warhammer-giveaway-results/
The give-away has finished.
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