The code that produced the below graph is released! Hotrepart was basically done a month ago, but I decided that releasing code into the wild, especially code that is supposed to start conversations, is probably not the best thing to do at the same time as organising my own wedding. I'm happily married now :-) Hence the release.
This is an ongoing project that I don't intend to let rot, like I did with Gradient. There are several things to do off the bat: another patch to PL/Proxy, then configuring EC2 to run Postgres nicely, then coding up some intelligence to trigger the repartitioning. Amazon releasing autoscaling just made that a whole lot easier.