Reuters takes a look at the declining success of music games like Rock Band and Guitar Hero in 2009.

According to data from market analyst NPD Group, sales of these games haven't met expectations. The Beatles game, while selling a respectable 800,000 units of its various versions so far, missed the 1 million mark analysts expected in just the first month after its September 9 debut. "Guitar Hero 5" sold 500,000 units in its first month, compared with the 1.4 million "Guitar Hero III" moved two years ago in its first month. "DJ Hero," the game that was meant to expand the category into the hip-hop genre, moved 123,000 units in the first few days after its late-October release, and analysts at Cowen & Co. slashed their sales forecast for the game from 1.6 million this year to 600,000.

The article is based mostly on comments from analyst Michael Pachter. Plus, it doesn't take into account the revenue earned selling downloadable songs. Which is a bit like not understanding that printer manufacturers make money selling toner cartridges.

Also in the article is this tidbit about my favorite game of the year.

The game with the most impact on sales was "Brutal Legend" -- which isn't a music simulation game but an action/adventure title with a strong heavy metal theme and soundtrack. But while songs from acts like Motorhead and Judas Priest saw sales spikes as high as 700 percent, the volumes were too low to make much of a real impact -- in many cases from single-digit or double-digit weekly sales to low triple-digit sales.

Take that, Guitar Hero: Van Halen!