 Activision Publishing chief executive Mike Griffith , in response to questions about Activision 's approach to the Guitar Hero market , noted that Guitar Hero continues to <unk> the Rock Band series in both number of sales and revenue , with consumers continuing to buy the separate games on the market , and considered the market acceptance of the multiple games as <unk> for their model . Regardless , after releasing 25 different <unk> ( between games and bundle packages ) in 2009 , Activision opted to reduce that number to 10 in 2010 , recognizing the music game genre was not as profitable as it once was . Activision later opted to put future development of the series on hold in early 2011 citing weak sales in the rhythm game genre , a move that many journalists attributed to Activision 's earlier <unk> . 
