I've been using Apple's Server.app (Formerly OS X Server) for quite some time now at my home. Its definitely a bit of work to maintain, specifically on the CalDAV and CardDAV integration. But failure is something I would hardly attribute to the setup. It's certainly not any worse to use than configuring and maintaining Postfix/Dovecot/Roundcube and CalendarServer individually.
In what way would you suggest Apple's Server.app has failed (outside of the obvious hardware compatibility)?
I referred to MobileMe solution when pointed about Apple failure.
You are quite right on your opinion, but the question was whether is a viable alternative to Google Apps somewhere. And yet there is nothing on horizon except some distant plumes from Dropbox, and now I must add Podio and box.net.
