Do you realize that node.js is single threaded?
Having more than one process works fine for most purposes. Because the bottlenecks are more IO driven than CPU time.
Also, yes, I think concurrency model in node.js is the worst possible one.
I saw it. It's just a function to keep the main thread, ie. main() alive while the worker threads process the async events. Nothing out of the ordinary..
And why is it the worst possible one? Preforked threads per request are much worse as NGinX showed Apache