MTV Games/EA and Rock Band have the same dilemma Activision has with their Guitar Hero franchise. Video game sales are down year-over-year, and the story is even worse for the music genre, whose sales are down a whopping 46 percent.

Rock Band is giving it their best attempt yet at breaking Guitar Hero’s continued grip on the genre, though, with The Beatles: Rock Band next week, but the financials of the deal are finally coming out, and it s a big one.

From the LA Times:

Viacom will pay Beatles rights holders an unprecedented amount to include the band members’ songs and likenesses in the video game. It has guaranteed them a minimum of around $10 million and will shell out royalties of $40 million or more if the game sells as expected, according to three people familiar with the terms of the deal.

“The royalty rates on this are not even comparable to anything that has been done before,” said Martin Bandier, chairman of Sony/ATV Music Publishing, a joint venture of Sony Corp. and Michael Jackson’s estate, which controls the publishing rights to most of the Beatles catalog.

That equates to a helluva lot of Beatles fans buying a helluva lot of The Beatles: Rock Band to make this a profitable venture for MTV Games and EA. How much does the Beatles name bolstering the Rock Band brand worth in the long run, though