You've almost just described E (http://erights.org). The recipient of a message sent with "." must be in the same E process (called "vat"), while with "<-" the recipient may be remote (but needn't be) and the value we immediately continue with is a promise for the eventual result. (Each vat receives one message at a time and runs it to completion before taking the next off the queue, Actors-style.)

This was the language that taught me what Kay was talking about.