User blog comment:Jimeee/Skyrim 1.9 beta update adds Legendary difficulty and raises level cap (Updated Apr 8th)/@comment-5697729-20130322110310/@comment-184.100.217.187-20130322131343

If you are a PC user, you have to go to Steam and download it there.

If you are an XBox or PS3 player, you will have to wait for another week or two and it will automatically prompt you for download.