Maria-sama ga Miteru Fourth Season
Broadcast and Media: TBA
Source: Cobalt August 2007 issue (official Cobalt website
and official Marimite anime website
yet to be updated)
Based on the light novel written by Konno Oyuki and illustrated by Hibiki Reine, serialized in the Cobalt Bunko series, with 30 volumes released so far.
There are currently two manga adaptations, the Nagasawa Tomo version serialized in the the monthly Margaret (now The Margaret) magazine, and the Hibiki Reina version sporadically published in the Cobalt magazine.
Two TV and one OVA series anime adaptation have been aired or released. It is unknow whether the 4th Season will be a TV series or an OVA.