Earlier quoted context omitted.
I know it is not the mode to comment to mention your own up vote. Rails might have deteriorated in ease of use, but I cannot imagine it being worse than Java EE was in 2004. Modern Java EE is a world of pain, even simple apps are difficult to build. The entire front end stack is antisocial, difficult to extend and anachronistic. I don't think anyone working with a modern java web stack could read this post about rail…
Have you tried Java EE 6 ? JAX-RS in particular is a splendidly designed api for RESTful services. And then you can make single page apps instead of JSF. This method is even going have ide support in Netbeans 7.3 with wizard-driven Backbone/Angular app generation.
But, this isn't Sinatra vs EE6, its Rails vs EE6, so its not a proper comparison.
To compare with Rails you've got to look at other parts of EE6: JSF + CDI + JPA, which is an awful mess. JSF by itself is enough to kill its usability for many modern applications, the amount of state JSF carries around is ridiculous.