Beta was not fine until this point. We've had lots of issues, including server rollbacks, mass disconnects, and other problems.
At one point (I'm thinking beta 2?) everyone got disconnected but the game did not crash. This allowed me to run around and interact with the environment with no monsters up. Everything went swimmingly until I made the mistake of trying to talk to an NPC, at which point I locked up.
What is important to note is that the issue that has hit everyone this weekend is a completely new bug, and not an old bug that was supposed to be fixed in alpha.