A hero has fallen. Guitar Hero has officially died while iPhone games like Angry Birds and Words With Friends grow in popularity.

According to publisher Activision, which has called it quits on the music game division and plans to cease development of existing Guitar Hero titles, it's ending the series in order to concentrate on the online sector, especially downloadable casual games popular on iPhone and Facebook.

“Due to continued declines in the music genre, the company will disband Activision Publishing's Guitar Hero business unit and discontinue development on its Guitar Hero game for 2011,” the company stated in its latest financial statement.

“These decisions are based on the desire to focus on the greatest opportunities that the company currently has to create the world's best interactive entertainment experiences."

The news is hardly surprising as Guitar Hero: Warriors of Rock failed to bring in the cash last holiday season. It wasn’t the only rock game to disappoint in the market. DJ Hero developer FreeStyle Games has implemented severe layoffs, though there’s no word if the virtual disc jockey franchise will close up shop.

Don’t panic if you’re diehard for those virtual guitar riffs. During a post-earnings release conference call, Activision Publishing CEO Eric Hirshberg said the flow of downloadable content for Guitar Hero games will continue.

So why did the once crazy-popular Guitar Hero bite the dust? Well, shelling out $60 for similar annual updates plus $100 or more for new plastic peripherals is hardly appealing to Americans tightening their belts in the recession.

What’s more is that the releases seemed to come in quick succession, giving gamers little room to breathe. A plan for long-term profitability was ignored in favor of a rapid-fire approach. Consider the timeline of the barrage of releases:

Guitar Hero: November 2005

Guitar Hero II: November 2006

Guitar Hero Encore Rock The 80s: July 2007

Guitar Hero III Legends of Rock: October 2007

Guitar Hero Aerosmith: June 2008

Guitar Hero World Tour: October 2008

Guitar Hero Metallica: March 2009

Guitar Hero Smash Hits: June 2009

Guitar Hero 5: September 2009

Band Hero: November 2009

Guitar Hero Van Halen: December 2009

Guitar Hero Warriors of Rock: September 2010

To make matters worse, starting in 2007 the game had to compete with other Rock Band-type games as well as the DJ Hero.

Now, the question is should Call of Duty fans start to worry? The series certainly has had its own share of rapid succession releases. Every Call of Duty continues to be a huge hit so far — the latest, Black Ops, brought in a $1 billion in its first six weeks alone. And it's been around for two years longer than the Guitar Hero franchise. Yes, everyone seems to love guns.

But how long can the fascination last?

With simple games like Fruit Ninja and Angry Birds exploding onto smartphones only time will tell which direction the gaming industry goes.