We are currently tracking stability issues for some players with the latest build of the World of Warcraft: Mists of Pandaria beta. We’re currently working to address these issues, and expect to have a fix in place within the next 48 hours.

We will provide further updates when appropriate. Thank you for your patience and your participation in the beta.

Just a reminder:

Blizzard has a careful process for identifying issues, verifying and replicating them, coding the fix, and testing the results in a private quality assurance environment -- before deploying new software to users.