Very minor, but still:
The site description:
For for those using, extending or developing emacs
Has several problems:
There's an extra "for" at the beginning, of course.
"Emacs" should be capitalized, as it is a proper noun.
An Oxford comma would be nice ("extending, or developing"), although technically both ways are grammatically correct.
The longer description on the tour page and on the front page when not logged also needs to have “emacs” capitalized.