Haskell seems to be really nice for data structure transforms. A game can be modeled as such. But, it appears to me Haskell is used in programs which do a few large transforms whereas games do hundreds to thousands transforms per second. Games usually want to be mutable and using immutable language probably means there will be considerable effort in fighting against language features.<p>Ocaml and F# are more forgiving (some would say more practical) since they employ mutability as first class design element.