Guys at the RailsEnvy.com site has created a video comparing Ruby on Rails with Java. Actually they are comparing J2EE with ROR. It seems to suggest that to develop any Web application, you need everything from Hibernate to Spring.
But reality is slightly different. None of the technologies are essential. You can create industry strength Java Web application by using Spring DAO. Hibernate is not a must for it!
I do agree that being a recent framework, Ruby on Rails is an improvement in many respects over other frameworks. At the same time it may not be that safe to use it on a heavy duty site as the twitter debacle had shown.
Anyway I am not envious of Ruby or Rails. In fact I don’t understand the friction between Ruby and other languages. My advice is this, if you feel threatened by Ruby, learn it. :-) At the same time I don’t understand why some Ruby developers are so arrogant. I guess they have no practical experience in other languages!