The Top500 list remains interesting for many reasons. It's a map, for one, of emerging and diversifying economies. Saudi Arabia, for instance, was ranked 14th on the list with a 65,500-core system from IBM.

There are also many systems that aren't signing up for ranking. The National Security Agency, which runs some large systems, last appeared on the Top500 list in 1998.

But when Roadrunner broke the petaflop record last year, capable of more than one thousand trillion (one quadrillion) sustained floating-point operations per second, it brought supercomputers , which is a million trillion calculations, or a quntillion, per second -- a thousand times faster than a petaflop.

The petaflop was the big-bang moment for high-performance computing, and a similar, exaflop moment, is many years away, so focusing on it may mean missing the real changes ahead.

The revolution in truly accessible high-performance systems is just beginning.