"We were pleased to get a total of 42 applications, of which 19 merited serious consideration, and we eventually settled on a shortlist of 7 to interview. " 
Then there's the entire ecosystem surrounding Haskell, which is still old and antiquated (looking at you Cabal) and moving very slowly (interfacing to NoSQL or AWS, etc...).
> looking at you cabal
See this link for a solution: https://news.ycombinator.com/item?id=9766943
> interfacing to NoSQL
I recently used the Haskell riak binding in my day job for an application. The mongoDB package was uploaded "Tue Jan 19 06:04:06 UTC 2010"
There has been an AWS binding since 2011.
> Finally, the very high bar to just learn how to correctly program in Haskell puts it out of reach of 99% of the developer community.
A 10 year old can do it, so I'm sure more than 5% of the developer community can as well!
I wouldn't say I'm a spectacular programmer and I have both learned Haskell and used it in the real world easily enough. I will admit in the past there was a learning issue, but actions to make Haskell easier to learn have (and continue) to happen.
I'm looking forward to any rebuttals you may have to these! :)
Generally a good book, with some puzzling typos, IIRC (a year or so since i read it), he refers to Platform when he shd be referring to GHC
there's also recent books by Richard Bird and Simon Thompson, and the Haskell School of Music, which was recently discussed:
https://www.inf.ed.ac.uk/teaching/courses/inf1/fp/ (P Wadler)
also the Apress "Beginning Haskell" looks pretty good, tho the writing isn't perfectly clear. The example topics and sample code look good, and that's what mostly counts.
The books by Hutton and Simon Thompson ("Craft of FP" 3rd ed)are good intros as well. Haskell school of music is really good, but not sure for people who aren't versed in music topics (harmony/theory, composition, MIDI, DSP.