It quietly got patched into the game yesterday for NA and today for EU, Tok's Proving Ground which is a sprawling, huge Dungeon devoted to puzzles, yes puzzles, head scratching, mind frustrating, smash your keyboard off the wall puzzles.
Designed and built by the Master of fiendish puzzles himself, Dead Simon, this is going to keep players busy for many months as you can earn Rep with the Dead Simon Faction which allows you to craft unique, one off wardrobe sets which can't be obtained any other way.
This Dungeon is for the solo player and/or two players, no more.
You can see the Rift Community Blog here describing more:
http://www.trionworlds.com/rift/en/2...oving-grounds/
If you want a taste of what the puzzles look like and play like, you can watch Dead Simon himself run through them on a Rift Live stream from a few weeks back, warning, will contain spoilers.