The PlayStation Network will go under the knife next week, as Sony works through another bout of scheduled maintenance. From 16:00PM GMT on Monday 4th March until approximately 03:00AM GMT on Tuesday 5th March you’ll be unable to access the PlayStation Store, Account Management, and Account Registration.
You shouldn’t have a problem logging in and playing online, assuming that you’ve signed in recently. Trophies will continue to be stored on your console, and will be uploaded to your account the next time that you sync with the PSN servers. If you need any more information, feel free to refer to PlayStation’s official website – then come back here and have a good old moan in the comments section.