About 7-8 hours on my 4 minute videos, what with the various shots and the image overlays and the text overlays and the cuts. I really wish it'd take me less time, but it's good to hear I'm not the only one (': And it's great to hear that experience will drastically reduce your editing time, thanks Ninja and ChrisLegend!
Also, thanks xingcat and George Chen for the tips! Anyone else have tips on how to reduce edit time?