***Update***

Sony has finished maintenance on the PlayStation Network. You should now be able to go about your business.

***Original***

Sony has once again pushed back the timeframe for the PlayStation Network maintenance which began early Thursday morning. Several hours ago Sony expected it to be completed around 9:00pm PDT (12:00am ET); however, they have since delayed it until the wee hours of Saturday morning.

Sony's new estimate:

Maintenance is scheduled to end around 2:00am PDT (5:00am Eastern) Saturday January 19th.

Normally PSN maintenance doesn't affect most users who sign in 5 days prior to when it begins, but Sony acknowledged that some "authenticated users may have lost access" to many online features sometime during the maintenance.

It remains unclear as to what is causing the delay. All we know is that the current maintenance is "to upgrade the software" of PSN.