K-Meleon is a very nice browser, and I look forward to the new version, especially as you're obviously dedicated to getting it right rather that making it early (unlike some browser vendors).
Anyway, the one thing that's kept me from making K-Meleon my default Windows browser is that when I click back, (Alt + Left) the focus has moved. I don't like to use the mouse while surfing and that is really the one thing that really slows me down.
It would be nice if the Menu items (File, Edit, etc.) were keyboard accessible too, but that's not so important.