Haven’t upgraded to Mac OS X Snow Leopard yet? Congrats! Your procrastination might have saved your butt. The Apple Support forums are full of users who are reporting that all their user data has disappeared from a Mac OS X Snow Leopard bug.
Mac OS X Snow Leopard Bug
What’s causing the Mac OS X Snow Leopard bug? Apparently, all you have to do to accidentally erase all your data is to login into a ‘guest’ account. When you attempt to log back into your main user account, all your personal data will be gone.
If you are reading this now, and have Apple’s latest operating system, Mac OS X Snow Leopard installed, then disable the Guest account ASAP. This might be the worst Apple bug since the debut of Mac OS X.