This is simply fantastic. I always thought operational transformation was pretty difficult to implement robustly, but looking at Google's implementation lets you build interesting experiments without getting all those details right -- like building the world's best writing time machine. It reminds me of Cory Doctorow's approximation built on git: http://craphound.com/news/2009/02/13/flashbake-free-version-...

I think there are great possibilities for building on this idea...