Right up front: I do not want to start a religious war.
I’ve used vi for as long as I can remember, and the few times I’ve tried to pick up Emacs I’ve been so lost that I’ve quickly given up. Lots of people find Emacs very powerful, however. Its programmability is somewhat legendary. I’m primarily doing Solaris+Java development, and I’d like to ask a simple question: will my productivity increase if I invest time in getting my head around Emacs? Is the functionality that it offers over Vim going to be paid back in productivity increases in a reasonable timeframe?
Repeat: I don’t want a ‘my editor is better than yours’ answer. I just want a yes or no answer as to whether it’s worth investing the time or not. Will my productivity really increase?
I prefer emacs to vi, but I’m comfortable in both.
There are some things that you can do in emacs that make it more powerful than vi, but not all of them are even programming-related. (Can you send email or read news from within vi? No, but who cares?) If you’re comfortable with lisp (I’m not), you might be able to write add-ons and modes and stuff to make your life easier, but that’s just likely to be syntax colouring and brace matching and eye candy like that.
I will stop rambling now. Will your productivity increase using emacs? No.
Update: See my comment below. Since I posted this, I have come across ways that using emacs has made me more productive than using vi.