Luminus and LightTable (wow, that in-editor javascript demo) look pretty awesome.
Coming from Scala/Play my initial resistance to jumping the fence are: 1) lack of compile time type safety 2) odd, for me, language syntax 3) no ScalaQuery/Slick functional SQL wrapper equivalent
How is Scala-Clojure interop? Would be interesting to jar up existing Slick-based model layer and invoke within Clojure stack ;-)
Not having yet taken the plunge, based on the LightTable demo Clojure development seems pretty rapid fire (read: no waiting for compiler to catch up).
optional clojure type checking: https://github.com/clojure/core.typed/ (not finished, but showing promise)