I can only guess that jey's comment was downvoted because R is more prevalent language for statistics and data mining when compared to Python:

http://www.kdnuggets.com/polls/2011/languages-for-data-minin...

Thus, there is a much larger ecosystem as it comes to STATISTICS and data mining in R. Cluster analysis packages are especially advanced in R.

BTW, there is an effort to have OpenMP support in core R, e.g. the "dist" function:

http://r.789695.n4.nabble.com/How-to-safely-use-OpenMP-pragm...

EDIT: I was able to compile and run some of the functions under MacOSX 10.6 and R 2.13.1. I couldn't get it to compile with CULA (free version) and my GPU hardware is 1.1 so I can't run SVM :-(