Why does WCF ServiceHost stay open once out of scope?
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I was just tidying up some WCF (self-hosted) code of mine and realised that my ServiceHost object was going out of scope after it had been initially setup, but I could still connect to it.  

    public void StartMyService()
        {
            var host = new ServiceHost(typeof(MyService), new Uri("http://localhost:8000/MyService"));
            host.Open();
        }

If I call this again and to reinstantiate it and try opening it again, I get an error saying there is already something connected to the endpoint.  It only gets released now when the application shuts down.

I can only assume that the call to Open() does something at a lower level to keep it open in a *now* unmanaged way.   However, I can't find any information on this unless I'm just totally misinterpreting things here.