Diablo 3 servers with the Friends and Family beta run, where each of Blizzard's roughly 5,000 employees can invite five people to play. Of these 25,000 potential beta testers, at least one released screens of the beta program, which can be viewed on Diablo IncGamers.
Information about the limited beta run comes via the Russian-language B.net forum, which states that keys for closed-beta testers will be sent out only after an official announcement. There will not be an NDA for the beta, so once it launches we can expect a veritable flurry of information and screencaps. A flurry, we say.