Rails API Documentation

What makes the current versions bad in your opinion? Or, should I
say, what features are lacking? Is it the API documentation itself or
the applications running the online versions?

Have you look at http://www.railsmanual.com/ ? Or
http://caboo.se/doc.html ? Or http://www.railsapi.org/ ?

Between one of these three or the standard one at
http://api.rubyonrails.org/ , I don't think I would need anything