Here is an article that talks about it: http://kotaku.com/5850445/the-wonderful-distractions-sentient-glitches-of-skyrims-massive-world
I think it might be fun to know where one of these waterfalls are that kill someone from a fall, and lure an NPC to follow you near it, then turn around and shield bash him so he falls to his doom. But really I'm excited about all the little things in Skyrim I can waste hours trying things out on, and this is one of them. Throwing junk in the river to see how far it goes. I wonder if dead bodies will catch on trees that stick up out of the water? I wonder if I throw 10 in, will all 10 end up at the same destination? Do fish die from these falls? It's really not a big deal to me either way, but it's one of those things I will do when the time is right.