The closest one I know of is Haskell, but where Haskell can be superior in some ways in a single OS process, it gets totally spanked by Erlang when it comes time to leave one OS process, including going out over a network to other machines. And since you really need that if you want high availability, Haskell's out of the running for the systems I use Erlang for.
(Erlang is also much easier for other programmers to read.)
Haskell is also missing OTP. However, IMHO the more fundamental problem is that Haskell doesn't have anything like Erlang's fundamental, simple message passing, including process monitoring. Fix that and an OTP library just as good as Erlang's (or better) will fall right out; fail to fix that and it'll never catch up on that front.
(Erlang is also much easier for other programmers to read.)
Haskell is also missing OTP. However, IMHO the more fundamental problem is that Haskell doesn't have anything like Erlang's fundamental, simple message passing, including process monitoring. Fix that and an OTP library just as good as Erlang's (or better) will fall right out; fail to fix that and it'll never catch up on that front.