Thanks to a piping-hot, fresh build of the Second Life viewer, Massively has been able to get a better look at the upcoming content controls that are due in the next major release of the Second Life viewer.
As expected, there are now three content ratings available (though it is uncertain as to what their final names will actually be. Using "PG" as a content rating, for example, has legal issues): PG content, Mature content and Adult content.