Sales of "The Beatles: Rock Band" not great

"Sales of music video games plummet in 2009"

Excerpt:
According to data from market analyst NPD Group, sales of these games haven't met expectations. The Beatles game, while selling a respectable 800,000 units of its various versions so far, missed the 1 million mark analysts expected in just the first month after its September 9 debut. "Guitar Hero 5" sold 500,000 units in its first month, compared with the 1.4 million "Guitar Hero III" moved two years ago in its first month.

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To re-create the blockbuster sales of last year, the category needs a new innovation. One idea: Dahni Harrison -- the son of the Beatles' George Harrison, who worked closely on the development of "Beatles: Rock Band" -- told the Chicago Tribune he is working with Harmonix to create a version of "Rock Band" with new controllers that could actually help teach gamers to play guitar rather than just simulating the experience. Such new motion-capture devices as Microsoft's Project Natal may also play a role in evolving the gameplay.