Despite holiday 2008 growth that “fell short of many investors' expectations,” Cowen Group analyst Doug Creutz has rejected the notion that the music genre may be a passing fad.

“The music genre has expanded the overall video game market and is here to stay,” he said on Wednesday, although he predicted a moderate decline in genre sales in the US during 2009.

“We also believe that Guitar Hero is likely to face less competition from Rock Band this year, driving a gain in market share.

“MTV Games has decided to focus its 2009 development efforts on the release of a Beatles-themed expansion of Rock Band, rather than a new major edition of the core game.

“While the Beatles game will likely sell well and possibly expand the genre to new gamers/Beatles fans, we think the title is unlikely to achieve the level of sales that another major Rock Band release could due to the narrow focus of the title’s music.

“As such, we think Guitar Hero is likely to gain share in the core rock n. roll category of the music video game segment. Moreover, we think DJ Hero is likely to further extend Activision Blizzard.s share gains in the music genre, particularly given the possibility that there may be no directly competitive product in the market this year.

Creutz forecast Activision Blizzard music genre US sales growth of 0.7 percent year-over-year.