Bethesda has published the beta version of Skyrim 1.9, this release fixes another load of bugs and has two new features: a Legendary difficulty setting as well as Legendary Skills. The latter feature effectively removes the overall level cap, when you hit 100 you can make the skill Legendary. When you do this, the skill is reset to 15 and you are allowed to redistribute your perks to whatever skill you want, enabling you level up again. Full details about the changes in Skyrim 1.9 can be read at the Bethesda Blog.
With recent changes to Steam, you’ll want to take the following steps to opt into the beta.
Within your Steam Library, right click on The Elder Scrolls V: Skyrim.
Select the Beta tab and opt in using the drop box
If you opt into the Beta, be sure to back up your saved games or simply be careful not to overwrite your existing saves. If you decide to opt out of the beta program, your old saves will still work with the current release of Skyrim on Steam (v 1.8).
Legendary difficulty setting
Legendary Skills – Skills of 100 can be made Legendary. This will reset the skill to 15, return its Perks and allow the skill to affect leveling again. This effectively removes the overall level cap.