Each community has its own requirements and those of the Chef cookbook authors in general are different than those of Ruby library authors.
Lets say that I right a cookbook for apache2 on Ubuntu. What should I name the gem? Many other people will write this cookbook, particularly since mine only works for Ubuntu. Perhaps 'chef-apache2-ubuntu-btm'? Where do you store such metadata so a user can find, use, and contribute to a cookbook?
This isn't a simple solution and is a bit unique, which is why Opscode has been crafting a solution at http://community.opscode.com. It is easy to get a copy of a cookbook from the repository using 'knife cookbook site install COOKBOOK_NAME' and you can search the site through the web interface and using 'knife cookbook site search' to find the cookbook you're looking for.
The community site development has been slow, but continuous. In December we added source browsing so you can review cookbooks without downloading them.
http://www.opscode.com/blog/2011/12/14/chef-community-site-c...
There's still much to do, but I think we're (I work for Opscode) headed in the right direction for the project and community.