But the numbers were a good gauge of market movement and demographics that were before not transparent. Seeing surprising unit sales for software and the impact, or lack of impact, on hardware of certain titles put many myths and misconceptions to rest. For those interested in the industry as such this is a sad move because NPD was consistent in release schedule as well consistency of how they generated data. It also covers the biggest single market.
Unless you're actually making and marketing games, what good does that information do you? It can be interesting to see what people like, and see games surprisingly bomb or rip up the charts.