You might want to change your Thursday multiplayer plans.

Starting Thursday, January 15 and 9:00 a.m. PT and going until 1:00 p.m. PT that afternoon, access to the PlayStation Network will be limited.

According to Sony, the downtime will allow for the deployment of, "a series of back-end improvements to the network." Applications like Netflix will still function, as well as online play (at your own risk, of course), but the PlayStation Store, PlayStation Home, and the ability to manage your account will not be available.

[Source: @AskPlayStation, PlayStation]