Seems nice except for how it keeps pushing you to login to github, that would probaby get annoying after a while if working with non-github repos. Also the diffs weren't working with the java files I tried it with, it just minuses and plusses the whole file, hopefully just a bug they can fix. This is my first look at a Windows 8 UI and if this is representative of the fufure I am worried, but it does looks pretty. Overall though this is a good effort.