Activision, whether you agree with their developing practices or not, are raking in the sales. For the September quarter, Activision Blizzard was the top third-party Nintendo DS publisher, according to the NPD Group. Guitar Hero: On Tour took the number one best-selling spot overall for DS in North America for the September Quarter, as well. It's doubtful the next Guitar Hero for DS will sell as well as On Tour did, especially considering the looming DSi release and its loss of a Gameboy Advance slot..
Source: GoNintendo