
Not that big of a deal.
Other companies have done this, mainly in the U.S.-- one that I know of is "Skyhook Wireless", which is the database that Apple was/is using to make the "Locate Me" feature on your iPhone work much faster. The iPhone scans nearby WiFi hotspots, then looks up their lat/long via Skyhook's database, giving them a better point of reference to start finding you.
I have made a public interface for checking if your router's MAC is in Skyhook's database: http://www.pdsys.org/skyhook-lookup/