Ross Ihaka was my supervisor for my honours dissertation last year. Reading this article was a bit amusing for me. If you asked him for his opinion about R, let me say he wouldn't have written such glowing words about it! He doesn't like being in the limelight all that much either, from what I have been able to tell.
I may have some idea what is meant by the "wanting to create more advanced software" at the end of the article. At the moment he is tinkering away rebuilding the guts of R in Lisp. He reckons if "things were done properly", R would be orders of magnitude faster and more efficient. For example, when fitting a linear model, several copies of the data matrix are made when performing the matrix operations required to find all the coefficients, working out diagnostic matrices, et cetera.
So if anyone out there wants to contribute to R, now would be a good time to volunteer.
Arithmetic is being able to count up to twenty without taking off your shoes. -- Mickey Mouse