There are 14 or 15 emergency vehicles directly across the street from my Manhattan apartment building (see the highly impressionistic view at left).
We're located between two sizable hospitals and there's a firehouse nearby, so sirens are a regular thing... it's remarkable how quickly they become part of the white noise of the city. I do a weekly radio segment on an Atlanta-area radio show and the wailing has become a running joke. I know it confirms their worst ideas about New York, so virtually every week I hear myself saying, "Just so you know, that's an ambulance going to the major hospital center a couple of blocks from my apartment..."
But I have to say, I'm a little unnerved by the sheer volume of flashing lights outside my windows just now. Not so unnerved that I'm doing anything about it, though.