Rails and JRuby

Hello friends.

I'm investigating building a Rails stack with JRuby as the interpreter. I'm a little confused by the choice of Tomcat and Glassfish. Which is being used most frequently for greenfield set ups? Also, for Glassfish, are people using Prelude, or version 2?

I also wouldn't mind some hints with respect to how Capistrano or Vlad fit into the equation.

Our current stack uses MRI/Phusion/Apache.

Thank you for your time,

James H