Can 'Rock Band' Unplug 'Guitar Hero'?

Music-based video games are likely to top off the wish list for most gamers this holiday season. In the spotlight will be two upcoming games that define the genre: Activision's(ATVI) Guitar Hero III and Rock Band by Electronic Arts(ERTS).

Competition among Activision and EA is fierce, and in an interesting twist, the same studio, Harmonix, a division of Viacom's(VIA) MTV Networks, has created both games.

In 2005, then as an independent studio, Harmonix, fashioned a guitar-shaped accessory that gamers could use to play along with their favorite artists, resulting in Guitar Hero. The game was published by Activision, and its success turned Activision into a stock market darling.

The original Guitar Hero game went on to sell more than 1 million copies, and its sequel, Guitar Hero II, has sold more than 3 million copies.

In September 2006, MTV bought Harmonix for $175 million. By then, Electronic Arts had lured the studio into a partnership, and Harmonix started developing Rock Band, the successor to Guitar Hero.

The revenue split between Harmonix, its parent, MTV, and EA for Rock Band hasn't been disclosed.

Activision's in-house studio, Neversoft, is developing the third installment of the Guitar Hero franchise.

Rock Band has been described as Guitar Hero on steroids. The game comes with three different instrument-based accessories -- a guitar, a drum-shaped controller and a microphone for a lead singer.