Come! Let us climb the Mountain of Death!

So, this image has be mauling me for quite a while. I finally have it to a place that I am ok with, but it looks like utter crap on the web for some reason. Looking at the same image with other programs presents no problem...anyone care to explain that to me?

I've lost a ton of the variations in color and all the subtle things that took me forever to do...
Hope it looks ok anyway, though.