So parallel Haskell is around 60x Python here, and 150x faster than Ruby. And there was basically no difference in development effort required. Which high level language would you choose?

http://donsbot.wordpress.com/2007/11/29/holy-shmoly-ghc-haskell-68-smokes-python-and-ruby-away-and-you-can-parallelise-it-for-free/