This kind of thing really appeals to me, I'm very tempted to give it a try.
I have tried emacs and vim a few times, but the problem is that I don't want to use them for everything, and I have trouble getting my head around two totally different ways of working. I recently did a check of the programs I use in the average week. The current list is (in no particular order)
* XCode, for Objective-C / iOS development
* Eclipse, for C++ / Android
* Apple Mail
* Chrome
* TeXShop, for Latex editing
* Sublime text, for other bits of C/C++
* Vienna, for RSS reading
* Evernote, for document ordering
* Wunderlist, for todo lists
And what is great is that all these apps share 90% of my frequently used key-presses. In particular, I'm never at a loss as to what quit/find/open/save are. Each of these tools I have found the best at what they do.