Compare where the two languages were, and look where we are now.. Lambdas? C# got them later. Immutable constructor patterns? C# got them later. A scripting

Compare where the two languages were, and look where we are now.. Lambdas? C# got them later. Immutable constructor patterns? C# got them later. A scripting environment? C# is trying. Pattern matching? C# is trying (but since it's not exhaustive...). No nulls by default? C# got it later (and less clearly). It's really impressive how quickly those features have gained mindshare and become 'must haves' despite initial resistance. Fundamentally, though, the higher order programming features that F# inherits ML give it a maturity and flexibility that C# will just never encompass.