What's required for Exascale

I've been watching the google results for the key word "Exascale"... and found this at the bottom of this article about bioinformatics. (Emphasis mine)

And in another opinion piece over at International Science Grid This Week, Irving Wladawsky-Berger, a 37-year IBM veteran, lays out some of the big challenges on the way to achieving exascale computing. Whereas the evolution from terascale to petascale went smoothly using tens to hundreds of thousands of processors from the PC and Unix markets, they will not get us to exascale, writes Wladawsky-Berger. Exascale will require some other kind of major transition in chip architecture, not to mention a completely new programming paradigm. 

Well... that is precisely describes the Bitgrid, or will, once I get the thing built.