According to the Google Ngram corpus, R is still the top rated statistical software package.
Ok, I’m just kidding. That plot is worthless. All the data are from books published between the years 1890 and 2008, and none of those software packages would show up in books until possibly the mid to late 1990’s.
For a serious comparison of statistical software packages, scope out Robert A. Muenchen’s “The Popularity of Data Analysis Software”.
If you want to explore more with the Google Ngram data, check out my Rook application. It’s a total hack. I’m using Apache to proxy to nginx that proxies to a bunch of R instances running my Rook package. The application is running an unreleased version of R, using an unreleased memcache client in R.
The good news is that I found and fixed a bug in the internal R web server.