World Tour has sold about 1.5 million (about 55% fewer than it's predecessor) in the US while Rock Band 2 sold about 809,000. This is disturbing industry analysts since in the gaming world, sequels usually sell better than the original.
Overall, music games are down by 6% from 2007 but still hold a 16% market share in the gaming genre, making it the top-selling category, according to research group NPD.
It could be a sign of the economic times, or it could just mean that music games have run their course. That being said, figures just released indicate that Guitar Hero II is the biggest selling game ever, with sales just over $1 billion.
The bet here is that this fad is on the slow wind down, only to be accelerated when the next new thing comes to the public's attention.