From the last live stream Jon mentions that he would like to run up to 1 million units, with either 1500 or 15,000 units per core (I forget which, but its in the first half of the stream if you want to look it up). Although the 1,000,000 mark sounds more like an aspirational goal, than something which they currently support.
64-cores * 15000 units = 1,000,000 or so And yes it's more of a design goal than anything. If you don't shoot for it you won't make it.
I saw the livestream.. so basicly 4 of those CPU's would go a long way to reach the goal you guess? And no, I aint gonna buy them just to try out :lol: