> That means that someone manually took the site down.

Since the News.YC code (which NewMogul also uses) runs in a single Scheme process, it could have shut down for any number of reasons: it might have crashed, failed to start after a server reboot, been killed by the OS or hosting provider due to a memory leak, etc.

I don't know what kind of monitoring nickb might have set up, but if he's not responding to personal email or phone calls, it seems reasonable that he simply doesn't/can't know that the site is down.