swank-clojure 1.2.0 made the setup process much less painful. Yes, you still need to install Leiningen and Emacs manually. After that, (1) an experienced Emacs user can install clojure-mode and SLIME manually, or (2) anyone can use ELPA to install those two modes. Those are fairly easy tasks, and don't require much tweaking.
swank-clojure 1.2.0, which was always the hardest part, does not need to be installed manually. It just gets listed as a dependency in project.clj, and after that "lein swank" on the command line does magic.
The process has gotten a lot easier and Leiningen has made things way easier. lein-swank is just dreamy and comes close to providing all that nifty class-path handling functionality that something like Eclipse provides for Java. A lot of great work has gone into things like swank-clojure and Leiningen and it's amazing that the Clojure community has pulled together such a great set of tools in such a short period of time. There are languages on the JVM coughScalacough that have been around for a lot longer and really seem to be lagging behind in terms of tools.
swank-clojure 1.2.0, which was always the hardest part, does not need to be installed manually. It just gets listed as a dependency in project.clj, and after that "lein swank" on the command line does magic.