This appears to be limited to work (though I haven't tried this anywhere but at work and home -- home is Comcast). At work I get the South Central data center. The only thing "south" about my location is that I'm in Southern Washington State (Vancouver).
I'm not sure what good telling you the IP address of my work's internal DNS servers but I'll see if IT can tell me who they forward to. Here's the IP's it's resolving for channel9.msdn.com: