When Erlang was designed/invented the goal was never to make a new language, the goal was to design a way of building systems with a set of specific characteristics, massive concurrency, fault tolerance, scalability, etc. One part of this was the language, Erlang. But at the same time we were developing the language we were also looking at how you would use the language and its features to build such systems. The language and the system architecture went hand-in-hand with support in erlang for the type of patterns you would need in the system architecture.
These ideas and patterns existed before OTP. So there were Ericsson products built on top of Erlang which used these ideas and patterns before OTP. OTP "just" took these ideas and design patterns and formalised them in a generic, cohesive way. Plus of course a lot of useful libraries.
So we were never really out to design a functional language based on the actor model, we were trying to solve the problem.
(We had actually never heard of the actor model but were told later that Erlang implements it)
Funny, I recall some surprise in the community because Joe was asking some easy question about C for some glue code. It's been 5 years since I touched Erlang, only for learning, but is message passing style and the way you create functions like in prolog (or in Shen or picolisp) is unique and a great virtue. I know that tcl has secure interpreters, I wonder if there is such a think in erlang.
There is also a mailing list at https://groups.google.com/forum/?hl=en#!forum/lisp-flavoured... and an IRC chat at #erlang-lisp.
P.S. I also have a prolog running on erlang as well.