I've started already! https://bitwasp.co/block_hashrate.php

So basically, I'm doing as I described above.. Get pools % hashrate, determine based on their hashrate how many blocks deep a transaction must be so that pool to have less than 1% probability of producing a greater difficulty chain..


code's here if that's any use to you, PHP: https://gist.github.com/afk11/bbd9657b91e9a68d054f