Finally some Endgame info

http://www.pcgamer.com/2012/12/20/battlefield-3-end-game-pack-to-include-vehicle-dropship-dirt-bikes-capture-the-flag/

Four new maps designed for high speed combat and action
Three new vehicles including the fast and agile dirt bikes
New dropship provides support to ground troops with vehicle drop capabilities
Return of the classic Capture The Flag game mode