April 30th update. (source: http://www.guildwars2guru.com/news/1119-flame-frost-retribution-updates-guild-missions-wvw-abilities-new-gem-store-items/)
April 30th will introduce a slew of new content, including a new dungeon (complete with its own unique rewards)
In addition to the events that will be added throughout the world, there’s a new dungeon that players will be able to experience. Unlike the original set of dungeons, this dungeon has a single main path; however, the dungeon itself will change upon re-entry. Voice-over dialogue will alternate, enemy combinations will change, and even the location of the dungeon itself will vary. New mechanics and challenges will also make their way into the dungeon to provide a fresh new challenge for everyone.The developers also made note of a unique instance of the dungeon that contains new dialogue and cutscenes to provide closure for the entire Flame and Frost story arc.
So to close off flame and frost story content, we get a whole dungeon, with 1 path dealing with the dredge/ flame legion alliance specifically. New rewards for the dungeon, a seemingly different method of having players experience different dungeon paths, so they now are given a varying path each time, rather than choosing.

they are trying some interesting things we will be keeping an eye on.