Harmonix, the original Guitar Hero developers, were trade by Activision in 2006. However, since then, Harmonix have developed the Rock Band series, a series that has produced heavy competition for Activision in the music game genre. Now, almost four years later, Bobby Kotick, Activision CEO, says that letting go of Harmonix was a mistake.

“We had always known them as sort of somewhat a failed developer of music games. They always had really great ideas but nothing that was really commercially viable until Guitar Hero. And [we thought], it’s a good piece of software, and if we gave it to [Activision-owned Tony Hawk development studio] Neversoft, they’d knock the ball out of the park with this,” he said — according to Kotaku.

“We really didn’t even think, ‘Hey we should go to Boston, and meet these Harmonix guys and see what they’re up to.’ And, of course, if we had gone up, I think the world of Guitar Hero would have been rewritten. It would be a lot different today. And it would probably be a profitable opportunity for both of us and an opportunity where you’d have even more innovation in the category.”

“A lot of times when you get caught up in the financial details of the business, it makes you overlook what’s really important, which is who’s passionate, who’s committed, who’s inspired and where’s the next idea going to come from,” he continued.

FreeStyleGames studio, the developers behind the upcoming DJ Hero title, have been hinting at the possibility all of E3, but the developers over at Neversoft, known for the Guitar Hero series, haven’t put their two cents into the equation, until now.

“We’ve worked with [DJ Hero creator FreeStyleGames], talked to them about the game for a couple of years now, looked at different builds and played it,” GH director Brian Bright told Eurogamer TV. “We would love to integrate in the future.”

However, Bright went on to say that the games release dates did not allow the team to include the option in the latest major Guitar Hero installment.

“Unfortunately for Guitar Hero 5, we ship a few months before they do. [But] we’d love to explore instrument compatibility in the future; we’ll see where it goes.”

Altogether the music video game genre was down six percent in dollar sale for November, but the Guitar Hero and Rock Band franchises still remain on the genres top. But, unfortunately for EA, which has been suffering of lately, Activision’s property has simply proven itself to be the most popular.

“We should note that while the Rock Band franchise managed to grow in November, Guitar Hero overall still outsold Rock Band by more than 2-to-1 in terms of dollars in November and almost 3-to-1 in terms of units,” which was pointed out by UBS analyst Ben Schachter.

Anyway, the company behind Guitar Hero, Activision, can’t exactly be “jumping for joy.” Activision should be concerned since the franchise did see some significant declines last month.

“The biggest concern around Guitar Hero has to be the fact that Guitar Hero World Tour (12 SKUs) declined 48% in units and 31% in dollars from Guitar Hero III (6 SKUs) on a year-over-year basis. This will fuel concerns that the genre is past its peak,” Schachter added.

“With Activision and others sure to bring new innovation to the genre next year we can’t count it out, but it almost certainly won’t be the growth driver it has been over the past two years.”

[Guitar Hero easily beat Rock Band in November... via Game Daily]