I think it's just for that one area for that page.
Looks like they will give you the code to setup in any area you want. if you have your own ModeS/ADS-B equipment. http://www.frontier.nl/index.php?url=index.tpl&p[page]=casper
Flightaware is good too. But we can discuss that in another topic with a better title. So we don't hi-jack this topic