Why though?
Cursive has a working debugger while Emacs doesn't.
Emacs has a lot of stuff outside the realm of Clojure, like irc mail and orgmode, but Cursive really is the more advanced Clojure environment.
Even @dnolen seems to have switched to it.
Maybe it's just my 4gigs of RAM speaking, but Cursive is sluggish and heavy. I have Emacs running in a drop down terminal, that I can hide and show fast, I can run many languages simultaneously (Python and Clojure for me), I can quickly navigate and to all sorts of things without any load time. Everything feels very effortless, thus why I'd recommend Emacs. Not to say that I am above opening up Cursive for serious refactoring or navigation. :)
