The eagerly-awaited beta has begun! Time to start spamming your inboxes :)
The fiery gates leading to the Burning Hells have begun to swing open, and the Diablo III beta test is officially underway. Invitations to participate in the beta test are now being delivered to the chosen heroes. As with beta tests for other Blizzard Entertainment games, the testing process for Diablo III will occur in phases. In addition to selecting players who have opted in via their Battle.net accounts, we’ll also be providing keys through beta promotions and giveaways -- stay tuned for more info.
Unofficial word around the traps on a few sites is that the closed beta allows play of the five classes, a fully-functional portion of the Act I experience including facing off against the Skeleton King.
Check out the official post
on the Diablo 3 blog for more. promoted/edited forum item