Want to play Diablo 3? Players on Reddit have noticed that it's possible to download the client and jump right into the game even if you haven't received a beta invite. Blizzard haven't mentioned that they're opening up the beta, so it could be an accident. Either way, it's out there and people are apparently playing it. We've dropped Blizzard a line to find out what's going on.
Update: the Battle.Net servers now seem to be down for maintenance. Lots of players on the Battle.Net forums mentioning that they got some time in before that maintenance period kicked in. Blizzard community manager Nethaara posted a short while ago to say "the Diablo III beta is currently unavailable while we work to resolve an issue." They promise another update in a couple of hours.