5. Rails Documentation (that is why some websites have FAQ’s if they can’t solve your problem, then you might have a bigger problem)
6. Scalability Options (do they meet your demands presently and for the future?)
7. Pre-installed Gems (much better if they already have this)
8. mySQL, PostgreSQL and SQLite Databases (options are better than no choice at all)
9. Subversion, Trac, and/or Buzilla Hosting (company that supports developers are good companies)
10. A Website or Applications of Their Own Developed with Rails. (a good sign that they mean business with a framework)