There is no new functionality - only design. I am reading Testing Applications on the Web (by Hung Q. Nguyen, Bob Johnson and Michael Hackett) and the chapter about design and performance made me think about software target users. So I decided that testers (and all IT users) will like so called terminal design with dark background and monospace font.
Also I am using now new text editor Atom. I'll write about it later when I get enough experience with it.