It's not a good thing for anyone. Free exchange of information is one of the best things about the Internet, and critical to a robust debate. Anything that cuts back on sales information available to the public is a step in the wrong direction. It's extremely shortsighted to see this only in terms of a gain for vgchartz; whether or not the NPD numbers were more accurate, they were widely accepted as more "official", and thus a useful metric for comparison. I'm extremely disappointed that the group wants to go back to being a secretive black box, accessible only to the privileged few. Historically speaking, that has rarely worked out well for companies, or societies in general.
Too bad there's not another "official" chart-tracking service for America. Look at Japan - the fact that both Famitsu and Media Create track sales means that neither one could ever get away with something like this. Of course, if vgchartz can continue to improve its accuracy, NPD should become less and less relevant as time goes on (which they deserve, if they're going to act like this!)
End of 2008 totals: Wii 42m, 360 24m, PS3 18.5m (made Jan. 4, 2008)
