Believe it or not, the PlayStation Network is undergoing maintenance later this week, and as per usual, it seems to be of the standard sort.
"During this time, we will deploy a series of back-end improvements to the network," Sony says. The service will be impacted on 15th January, and the maintenance will last four hours, from 17:00PM GMT to 21:00PM GMT. However, in a post on its support site, the Japanese company states that "if you've signed in to the network any time prior to October 8th, you will be able to play games online and access partner apps such as Netflix during this maintenance period". See, it's not so bad.
You won't be able to access the PlayStation Store, Account Management, or PlayStation Home while the service is being tampered with, though, so make sure that you're not planning on nabbing some downloadable goodies during this time.