I think it depends on what people are using their editor for whether they'll jump ship. I started out on vim, and I really loved it. Then I was typing up papers using the vim latex suite and syntax highlighting would cause my machine to choke every time I scrolled through text. I could have just turned off syntax highlighting, but I tried emacs and auctex, and it worked wonderfully. Since then, I found a bunch of other things that I prefer about it, and only really use vim for quick config file edits. Now that I've been playing with it for a while, chords are second nature, just like modal editing became for me with vim.
I imagine that nobody who's terribly accustomed to either editor will switch unless they've got a specific need their current editor doesn't meet.