I just helped a person out who got stuck at section 4 Networking who did not know how to edit/create a file. I checked the docs and the first mention of nano is section 10. Bug 18651 discusses this and is marked resolved. I think that a short blurb at the beginning of the guide would be best stating that nano is the default editor and include the link to it's guide as well.
Indeed. I'll add this to the docs...
Fixed in CVS.