Clojure Reader Conditionals

So Clojure is getting Reader Conditionals ie. a way to put Clojure / ClojureScript etc. variants into ordinary source files.
It’s like .cljx files but without the separate pre-processor. Now the Clojure / ClojureScript compilers themselves will be able to pick out the variant of the code relevant to them.
Most of Patterning’s core is in .cljx format. I’m looking forward to moving to .cljc but it seems like this feature is so new (only in Clojure 1.7) I’d be better waiting a bit longer.