Tapestry, Wicket and Appfuse? You're making my point for me: The thinking you're using now to praise Rails and attack Clojure would have been just as valid seven years ago to praise Java and attack Ruby. All you're really remarking on is the maturity of the communities in question, but you're presenting it as a commentary on the usefulness of the technology.

And Clojure has been known for a good two years now, but I would not have said Clojure was popular two years ago. It didn't have a lot of regular users, which is what you're observing when you say people aren't solving "real problems" in it. I'm not sure I'd even say Clojure is popular today. I'd say it's still roughly where Ruby was in 2004 — lots of excitement, but still lots of growing to do.