Video games for music lovers aren't what they used to be. Both Rock Band and Guitar Hero are billion-dollar franchises, but their sales in 2009 fell to a small fraction of their glory days. The initial rush of adrenaline from strapping on a Guitar Hero or Rock Band guitar has gone away, and the latest iterations of the genre from Activision Blizzard (Nasdaq: ATVI), Viacom's (NYSE: VIA) MTV Studios, and Electronic Arts (Nasdaq: ERTS) are falling on mostly deaf ears.

That might change this holiday season, though. Rock Band 3 has spent two years in development hell, and the near-finished product looks like time well spent. Your band can now feature up to seven members, including three-part vocal harmonies and a two-octave keyboard. More importantly, the development team is taking pains to make the game experience closer to what it feels like to really play the instruments.

At this point, you might wonder why you shouldn't just buy a real guitar and take some lessons instead. The studio hopes to answer that question with a resounding "fun for the whole family!" Playing real music is hard, dude. Here, you can set the difficulty according to each player's ability, and slip off for a bathroom break in the middle of "Bohemian Rhapsody." It's a party game for party people -- though Fender will make a real six-string for Rock Band 3, and I can't wait to see how actual shredding translates into controlling the game.

Rock Band is more than that, even. The game has evolved into a publishing platform for hopeful musicians, and the more realistic control modes in this particular version also have the potential to actually teach you something about music. Imagine a soccer video game that leaves you winded and bruised -- but lets your  little nephew (or grandpa) play along without risking their shins. That's kind of the dream, and Rock Band is getting closer, even as Guitar Hero maker Activision has given up.

Rock Band 3 is coming to the Sony (NYSE: SNE) PlayStation 3, the Microsoft (Nasdaq: MSFT) Xbox 360, and the Nintendo (OTC BB:  NTDOY.PK) Wii in time for the 2010 holiday season. Publisher EA could sure use another multiplatform hit, and I hope Activision is taking notes on how it's done. But if the game is a real hit, the real winner will be Viacom, which runs the development studio and owns the right media platforms to market the game properly.

Music games have a proven ability to generate needle-moving sales, partly thanks to expensive accessories, and partly because they address a very large demographic called "music fans." The lightning has escaped from the bottle, but Viacom hopes to recapture it with more realistic gameplay. Given that Viacom saw $13.7 billion in companywide sales last year, a resurgent Rock Band with billion-dollar revenue (or thereabouts) will make a real difference here.

Can Viacom revive the genre and regain billion-dollar sales? Is Rock Band 3 the correct prescription? Doctor, doctor, gimme the news … in the comments below.