http://www.youtube.com/user/TheHarley151?feature=mhee#p/u

Right, look about 5:30 into this video and there you will see corpses of a dragon, a bear and a mammoth, i killed about a week ago (game time)
they really annoy me, there are also some thieves in riverwood that are just lay in the middle of the path, can i get rid of them???

I think corpses go away a after a month after game time, apart from named dragons, which stay forever (I think, I'm not sure)

Yes, they also disappear if there are so many people on screen at once

Dragon Bones seem to move.

I killed one outside of Solitude, a little away from the boats, and when I came back, the bones were in the water.

Corpse seems to be blown away , but dead corpse in the cities... just stay for a really long time.

I like it. Adds realism. It would be more realistic if they rotted a little bit or had bite marks from scavengers, but i like it.
Also, TC, just move them lol. Hold A (if on 360) to move them around amd out of your way. Simple.

just hold in the search button and drag them away

I can top that.

When I was jogging outside of riften a Dragon skeleton fell ontop of me. (The first Dragon in the MQ to be specific.)