User blog comment:Jimeee/Skyrim 1.9 beta update adds Legendary difficulty and raises level cap (Updated Apr 8th)/@comment-5746798-20130311183617/@comment-68.118.33.232-20130313002135

It's rumered that it will be called Redguard, because Bethesda recently tradmarked that name. Which is the same thing that happened with Dawnguard, they trademarked it than announced it a few months later. The new update probably will reveal code for it as well.