NPD Group, a market
The new Digital Games Tracking Service uses point-of-sales purchases from publishers themselves as the source. Participating publishers include Activision Blizzard, Bandai Namco, Capcom, Deep Silver, Electronic Arts, Square Enix, Take 2 Interactive, Ubisoft, and Warner Bros Interactive Entertainment.
However, there are some important caveats to keep in mind. Most of these publishers will be providing sales data from Steam, the Xbox Live Marketplace, and PlayStation Network. Despite Activision Blizzard and Ubisoft's participation, though, data from Battlenet and Uplay are not included, respectively. Also, EA eschews Steam altogether, and it doesn't appear to be providing PC sales data from Origin.
Only participants will receive the detailed sales report from NPD, while the media will receive a new report a week later than NPD's usual posting date. The report will combine physical game sales as well as participating publishers' digital sales, giving an obvious leg-up to those publishers who have chosen to participate. Games that make the ranking without counting digital sales will be noted. In another notable change, game sales will be ranked by dollar revenue, rather than unit sales.
Publishers can opt
While it's great that NPD has finally decided to tabulate digital along with physical products, lacking digital sales from all publishers will skew the accuracy of reports. Nintendo, for instance, has yet to agree to participate in NPD's initiative. Being unable to factor in sales from the Wii U and 3DS eShop will leave a glaring hole in Nintendo's monthly numbers, and make it difficult to prognosticate on trends—one of the main reasons for NPD's existence.