Cool stuff. I love statistics and probabilities. I don't think "post-human" is going to be a dominant category. It may appear but somehow not sure how stable it would be. I think it would be more a "transition" form, much as archeaopterx was a "transition" between dinosaurs and birds.So, post-singularity one could have "half-man/half-machine" things running about no doubt. But there would be no point keeping DNA-based life around. The meme would have finally beaten the gene. I would say within a 100 or 200 hundred thousand years of the singularity hominids will be extinct, but "life-forms" in the form of replicating worms controlled by "minds" running on millions of machines at once, would be prevalent. These could perhaps survive until the heat death of the cosmos, or close to it, who knows. The key question I am not sure about is how long the "post-human transition form" would last. Maybe 10^4 - 10^6 years or so. Hard to narrow it down further tho.