The European PlayStation Blog
is reporting that PSN will be under maintenance today "from 17:00 until 19:00 on Thursday 8 September 2011, BST." On our clocks, that's Thursday from noon to 2PM EDT. The store, account management, and new account creation will be out of commission for that time.
These European outages usually translate to outages on the American side as well. To occupants of either region: if you have any PSN games you wanted to play tomorrow, you should go ahead and get them now. If that's too subtle of a hint, go get BloodRayne