While I agree that the former is a nice language, it doesn't compare favorably to Go as a development suite: the standard library is terribly designed, and the package management is rather poor compared to Go's (which is about as great as it gets).
Now there is "OCaml Batteries Included" which is supposed to mitigate that, but it appeared after I stopped actively using OCaml so I can't comment on that (incidentally, I dislike many of their choices).
Also Go has many of the features that make programming in ML a pleasure, many languages these days have them, which is a good thing.
Personally my tool of choice for many tasks would be OCaml with Go's package management system, and perhaps a syntax closer to M-expressions (like Mathematica).