Sometimes brothers have to fight one against the other for the same throne. Despite all the things that create a connection between them, the battle must take place. There is only one throne, one winner and… the winner takes it all, as ABBA was once singing.

The third installment of the popular video game Guitar Hero series and Rock Band could be considered at least step brothers, because although Harmonix Music System is no longer involved in developing titles in the Guitar Hero series, it was this company that brought Guitar Hero to fame. While Guitar Hero III: Legends of Rock was now developed by Neversoft, Aspyr Media, Vicarious Visions and Budcat Creations (depending on the versions), the old fans of the series will always remember that it was Harmonix that “invented” the game. This is probably what Harmonix itself believed when it started to work on Rock Band, which is also a music-themed game.

But, while Rock Band hasn’t been released yet, Guitar Hero III is already a popular game. And because in the video games industry there is only one throne too, analysts have already started to wonder whether it will be Harmonix’s Rock Band or rival Guitar Hero III that will eventually become No. 1. Part of the answer will probably come in the first days or weeks after Rock Band is released.

Until then, however, Guitar Hero III has become a real chart hit, as it has sold no less than 1.4 million in only six days on the market. Although Microsoft’s Halo 3 is still sitting atop the October Top Ten sales charts, the number of copies that Guitar Hero III sold for all video gaming consoles and for PC is more than the former sold for Xbox 360.

When Guitar Hero III: Legends of Rock was released this past Sunday, its fans had been already waiting for it for weeks. This is once again similar to Rock Band – its Xbox 360 version is to be released on November 20 in the United States.

So, we have two formidable competitors and one extraordinary musical battle to come. Rock Band or Guitar Hero III, which game will sell more? That is the question.