Greetings, I've solved a couple of bugs in the Leanpub markdown exporter (cross-links within the book using ids were not working, and footnotes containing a colon neither). As far as I can tell using Orgmode and Leanpub to publish books is now quite feasible, and produces rather nice results.
I have also published the sources for my book, The Hacker Ways, at https://github.com/juanre/hacker-ways It is rather annoying that github understands the org syntax but not quite, so the sources appear almost but not quite right. Clone and open in Emacs to see what's going on. Best regards, jm -- http://greaterskies.com http://juanreyero.com  Leanpub.com is a very nice self-publishing platform. I am not associated with them, and they are not responsible for my code.  http://juanreyero.com/open/ox-leanpub/  https://leanpub.com/hackerways/