Even after recovering from an extremely rocky launch that resulted in long stretches of downtime for players (even those who only wanted to play single-player) Diablo 3 and Blizzard are still facing some difficult issues.
The newest problem is that Battle.net appears to have been the target of a string of hacks which have resulted in users losing access to their accounts as well as losing gold and items. Bizarrely, the Blizzard Authenticator (essentially a password generator) doesn't seem to be effective in stopping the attacks.
So far, all we have are unconfirmed rumors though. Blizzard has not yet made any announcements about the attacks or made any account-safety suggestions for players. The current speculation is that Battle.net was the subject of an SQL injection attack, a form of website attack that attempts to ask the database to dump information (say, user account info) to an outside location. To be clear, the SQL injection rumor is just that, a rumor, and has not been confirmed.
The rumor persists because the timing of the attacks coincided with Blizzard bringing the European servers down for maintenance. Which some have taken to mean that the problem was on Blizzard's end, not the fault of the users.
The issue hit the spotlight when Eurogamer's Chris Donlan was the subject of one such attack. We don't currently know what the scope of the situation is, but now might be a good time to consider logging in to Battle.net, check for all your goods, then change the password.
Our friends over at CVG have been playing through Diablo III and here's 30 tips and tricks every Diablo 3 dungeon crawler should know