From the official site:
***PlayStation Network Down on March 3, 2011***
The PlayStation Network is currently down on Thursday, March 3, 2011.
We apologize for any inconvenience, but are working on the fixing the situation.
During this time you may:
* Not be able to access the PlayStation®Store
* Have difficulty signing in to the PlayStation®Network
* Not be able to play online games
* See a maintenance page when attempting to access the PlayStation®Network
Note: When you log into the PlayStation Network, a message may appear which states, "the PlayStation Network has been suspended". This does not mean that your account has been suspended; it simply means the PlayStation Network has been taken offline. Please wait until the maintenance window has passed before attempting to connect to the PlayStation Network again. We apologize for any inconvenience this may cause.
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