PSN maintenance prepares for Store return

Sony has confirmed the current PSN maintenance downtime is to help prepare the system for the imminent return of the PlayStation Store.
A new post from communications director Nick Caplin on the PlayStation Blog explained that the temporary outage represented a vital part of restoring the rest of PSN's services following the massive security breach last month.
"Starting soon, the PlayStation Network will be inaccessible for several hours for maintenance," he wrote. "The server maintenance performed at this time represents a crucial step in the full restoration for PSN, including the PlayStation Store.
"During this maintenance period, users will be unable to sign in to PSN, though those that are already logged in should be able to remain online.
"Resumption of full PlayStation Network service is still on track for this week in most regions. Thank you once again for your patience as we work to return PSN to the highest level of service."
PSN is due back online tomorrow morning at 7.00am, though it's unclear whether the Store will be back up and running then too.

Source: http://www.eurogamer.net/articles/2011-06-01-psn-maintenance-prepares-for-store-return

Source: http://blog.us.playstation.com/2011/05/30/full-psn-services-including-playstation-store-return-this-week/