[jhbadger]

"From a political perspective R was in the right place at the right time. It was a decent high level language that could handle matrix processing gracefully. Scipy/Numpy weren't ready for production yet. The others were Matlab, SAS, and Stata".

This is forgetting xlispstat, which was frankly the best of the lot. Free, functional (based on a subset of Common Lisp), and with dynamic graphics capabilities that R is now only beginning to match. But the problem I think was that it was maybe too early. In the 1990s, Lisp and functional programming seemed to be on the way out and object-orientation was the big thing (It's telling that the book on XlispStat is called "LISP-STAT: An Object-Oriented Environment for Statistical Computing and Dynamic Graphics", hyping the objects rather than the functional aspects). If it had come out now, with the current interest in FP/Lisp thanks to Clojure and Racket, it probably would have been more successful.