The inaugural State of the Game letter for The Secret World has been published on the official forums. The letter reveals that Funcom has plans to release new content for subscribers on a monthly basis beginning July 31st!
Monthly updates might include new missions, new weapons, raids, expanded character customization, new clothing items in the specialty shops, PvP dungeons, a dungeon finder tool (YES!), seasonal activities, new adventure zones (2 already in progress), cabal functionality, pets and/or combat enhancements.
The entire letter can be read on The Secret World forums.