I am quite literally building a full data analysis stack (as a product) in haskell, some parts of which will be available as a sort of proprietary augmented version of the haskell platform, and some parts are / will be open source.

I do think that there are compelling reasons to consider Haskell / GHC for analytical workloads, but depending on the details it really depends.

The principal cliff is just the HUGE number of (mostly poorly designed) libraries for many standard analyses written in R. Theres some nice engineering approaches to circumvent this, and theres some really exciting libs that a uniquely awesome and handy in haskell land.

A notable example is AD, a really easy to use auto differentiation lib by Edward Kmett, which has a really exciting refactor thats nearly done that will make it useable by mortal Haskellers :) http://hackage.haskell.org/package/ad and https://github.com/ekmett/ad (I've some neat bits i'll be hopefully adding to AD myself in the next month)