I am in the process of updating the Second Life servers to a new version in order to fix an exploit. The process began at 12:00pm PT, and should take four to six hours.
During this process, each region will be restarted once. Residents will be given one minute to move to another area before the region will go down. If you are logged out of Second Life at this time, please wait a few minutes and log in again.
Sorry for any inconvience this causes!