The Gentoo Linux vim tutorial is how I learned. It took me about an hour to become as productive in vim as I was in my previous editors (nano, GEdit, some random Windows editor, etc.) Everything past that was an improvement over any editor I have seen before.

I think it is a lot harder for people used to IDE's, but if you treat it as "get to the minimum productivity level as fast as possible, then slowly add more", you will probably enjoy it.