I was listening to CBC radio the other day and this is what I remember,its actually a funny story. Some random incident where back in the 50s somebody advertised a santa tracker and mis printed the phone number... which connected with Norad. After receiving a handful of calls Norad just started to play along with the kids that were calling in.

turns out there is also a wiki
http://en.wikipedia.org/wiki/NORAD_Tracks_Santa

*edit... Oh I thought you were asking, turns out you linked to the response...bah too much eggnogg...I should go to bed before santa realizes im up.