I use Chromium + Vimium, which makes my entire workflow possible from the keyboard when doing backend development. I somehow managed to go a full productive day at work without touching my mouse (except to move it out of the way at the start of the day) while working on a drag-and-drop feature. Since you're using the same setup, do you have a dotfiles repo so I can take a look? Mine is kind of messed up at the moment, but here's an old revision with everything: https://github.com/chris-ritsen/dotfiles/tree/113442a72ddacb...
I was using Vimperator for a while, but it didn't give good experience, My chrome has also its vim plugin but it has slightly different key map, because of that I stopped using vim plugin on both browsers.
I surely want to try out the new vim plugin Pentadactyl for firefox.