Activision has just announced ahead of its fourth quarter earnings call this evening that they will be shelving both the long-standing Guitar Hero franchise and True Crime: Hong Kong, which was scheduled for a 2011 release.

The official news follows a report on GamesIndustry.biz that reported that sources had told them that they would be axing both franchises and focussing the majority of its efforts on the Call of Duty franchise and Blizzard’s Starcraft and World of Warcraft.

According to the press release, because of the “continued declines in the music genre,” Activision’s Guitar Hero business unit will be disbanded and they will “discontinue development on its Guitar Hero game for 2011.” True Crime on the other hand seems to be all but cancelled, with the publisher announcing they will “stop development.”

“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,” says the press release.

"There will be no new music or skateboarding franchises in 2011," said Activision during the call.

The news will come as no surprise to anyone really, with music sales slumping in recent years and with Activision’s recent cost cutting rampage, which saw them announce the closure of Bizarre Creations.

Activision did, however, announce that Bungie’s property is still in their long term plans, and that, along with Call of Duty and “an innovative new universe with broad appeal that... will bring the world of toys, video games and the Internet together in an unprecedented way” will ensure long-term growth, enabling it to continue expanding its position as the largest digital publisher.

I wonder whether Activision have heard the saying about putting all their eggs in one basket...

More on this as it breaks.