This is an interesting concept and exactly the thing that dropbox is designed for (amongst other things of course) although I use it mainly for my business needs.
I have Mac (MB Pro) and Win (Mini Twr) systems as well and utilize them in the same way as you do in regards to TESO but have yet to think of a way to synch the updates of my concurrent addons. I will have to check this out.
Thanks for the great idea.
