I just wanted to take a moment and point everyone to two sites that discuss the development of new light pollution maps for the United States. Dave, did a review of satellite data from 2001 that results in darker skies in much of the U.S. vs the old maps which included snow on the ground, and that probably increased the light being reflected upward towards the satellites. This link takes you to Dave's new LP maps and a comparison of the old one with the new one. This link takes you to a wonderful presentation by Dave on CloudyNights in the Light Pollution thread about it.
I do have to say that though the colored zones don't match up exactly with my SQM data, sites can actually be darker than the colored listed from my findings, they are much closer to what I observe and record data in from my SQM than before. So go ahead, click on the links, read up and then see if your observing sites here in the U.S. have improved. Sorry, I don't think this has gone outside of the U.S. yet. :(