With Ruby on Rails, the web-application development had become really fast especially for mid and small sized applications. A lot of credit goes to the Rails Framework. But still Ruby lack what Java has, including innumerable number of utilities, packages, resources, Industry investment and acceptability.
Well, i guess after working on Grails i think we have got the right combination. Grails is built on Groovy and Hibernate. I liked GRAILS more then Stripes Framework also. We were able to develop web-application(small sized) at much quicker pace. It is more closer to Ruby on Rails framework. Provide Scaffolding and auto generating many of the code and functionality. It uses convention over configuration to the maximum. It has very easy to use and intuitive tags for Ajax implementation.
Here is the link if want to know more http://grails.codehaus.org/