The lack of higher-kinded types is somewhat disappointing, but considering F# is still effectively a FP bolt-on to the CLR it's impressive what they do have. P

The lack of higher-kinded types is somewhat disappointing, but considering F# is still effectively a FP bolt-on to the CLR it's impressive what they do have. Personally, I'm a huge fan of the ML-style syntax, in JVM land there is Frege but I'm less a fan of the full purity approach it derives from Haskell (I don't care how easy you say the IO monad is to work with, it drives me batty and I like to consider myself a pretty smart guy). Type providers, excellent async support out of the box, active patterns, there's a lot of great features in F# as well that make it worth looking at.