There will be one less video game to buy. Activision is pulling the plug on Guitar Hero. They’ve been a giant in the field since they debuted in 2005. But they will “discontinue development.” Harmonix is doing well with the competing Rock Band line. If you have Beatles Rock Band at home, you’re not alone. Big seller. And look for future Rock Band games this year with Johnny Cash and Bob Marley and the Wailers. Doesn’t get much cooler than that.