133w ago - Today Nyleveia.com (linked above) reports news of a security issue with the PlayStation Network 'Password Reset' feature, and as a result Sony has turned off the PSN sign-in to remedy the matter.
Sony has also confirmed that it was indeed not a hack, but a URL exploit that was subsequently fixed.
To quote from Community Team Moderator Yaster via the official PS EU Forum:
"Hey Guys. Please note that PSN sign in is currently unavailable for the following services:
• PlayStation forums
• PlayStation Blog
• Music Unlimited via the web client
• All PlayStation game title websites
Unfortunately this also means that those who are still trying to change their password password via Playstation.com or Qriocity.com will be unable to do so for the time being. This is due to essential maintenance and at present it is unclear how long this will take.
In the meantime you will still be able to sign into PSN...