Sony resets some PSN passwords
PlayStation owners unable to login to PlayStation Network due to an incorrect password may need to reset it. Sony posted the notice on the official forums, explaining, "We routinely monitor for irregular activity, and if such activity is detected, we may sometimes reset passwords of affected SEN accounts to protect consumers and their account information."
If you're not sure how to reset your password, Sony has provided step-by-step instructions which can be seen here. You will need access to your email address and date of birth associated with the account, otherwise you'll have to contact Sony for further assistance.
Sony has often been the victim of hacking, so it's nice to see them taking action to prevent such events in the future.