Nintendo's Wii was the best-selling game system in July according to NPD Group figures, helping the company achieve its highest weekly sales figures since December. Nintendo is rightfully proud of the DS, too, with its library of more than 300 titles, including the top-selling title Pokemon Diamond. The company is also touting the Wii's library, saying that it's averaged nine new games each month since launch, which is a faster rate than any of its competitors.