Sony have reset an amount of EU PlayStation Network passwords, forcing users to choose something new before they can re-access online features. That's inconvenient enough, but they've done it on such a scale that there's a huge backlog of people waiting for password change emails, and Sony has no idea when they'll be caught up.
In some regions, you're not able to change your password directly through the PS3. If you even see this as a solution, you're not in a region where the email backlog is causing problems.
Those in regions where this IS a problem: still no word on when the backlog will start to be cleared.