I have much more faith in the JVM but would like to see it provide a step beyond Rails rather than catching up. Play is nice because it is trying to accomplish this with Akka, though yes I see there are other issues. As mentioned in another comment, I'm kindof just wishing there was a cool Clojure framework. Maybe I will try one even there is not so much of a consensus as there are around these other emerging JVM frameworks...
Think Sinatra instead of Rails.
buuuut as retrogradeorbit points out.... the clojure macro system is powerful, so maybe it lends itself better to this type of setup
It's also a pleasure to program in Groovy.