Just seen this on the COD forums...
Announcement: PlayStation Network Scheduled Maintenance Show Details Hide Details Original Documentation: PlayStation.Blog
+ Posted by Patrick Seybold // Sr. Director, Corporate Communications & Social Media
PlayStation Network will be offline for routine scheduled maintenance on Thursday, November 17th from approximately 8am until 10pm PST.
During the maintenance, you will be unable to access the following services:
• PlayStation Store on PS3 and PSP.
• PlayStation Network Account Management.
• PlayStation Network Account Registration.
In addition, you will not be able to sign in to PlayStation Network from us.playstation.com. However, some users may be able to play online during the maintenance.
During this maintenance, you can continue to collect in-game Trophies and these will be updated on your profile once PlayStation Network is back up and running.
Stay tuned to the PlayStation Twitter feed for updates and a notice when maintenance has concluded.
We apologize for any inconvenience this may cause.