In his latest column on IndustryGamers, EEDAR analyst Jesse Divnich suggests that the growth of peripheral-based music games may have already hit the ceiling. With sales in the genre down 30% from last year, he compares Rock Band and Guitar Hero to the granddaddy of rhythm-matching titles, Dance Dance Revolution. Divinich makes a compelling argument that sales of the games may already be in a state of irreversible decline.
There are a number of reasons for the games to be taking a sales hit, but they all come down to the amount of innovation being seen in each iteration being staggeringly small. Peripheral-based games need to be designed with the hardware of previous releases in mind, limiting the amount of design change that can be made. Competing developers pumping out lower-quality games also force publishers to try and cash in on their IP with more frequent releases and the reduction in development time restricts the implementation of new ideas as well.
None of this is to say that these games will not continue to be successful, but the expectation that the audience for Rock Band and Guitar Hero will keep expanding as it has over the last few years is probably unrealistic. The question is, what more can anyone really do?