According to a story at GameSpot, industry sales tracker The NPD Group has released console sales figures for the top 10 best-selling games since January 2000, and Number Two on that list is Guitar Hero III.
Now, I think Activision would be justified in claiming that GH3 actually is the best-selling game of the decade, since the top spot is held by Wii Play, which is sold packed-in with an extra Wii Remote. My strong suspicion is that most of the 11.1 million people who picked it up (in the U.S.) probably looked at it as “Extra Wii Remote plus Free Game I Might Play.” But maybe I’m cynical.
Even so, GH3 is less than a million sales behind, with 10.3 million units sold in the States, which is a pretty nifty feat.
One thing to keep in mind, though: These sales only go through August, which means we could see a stunning upset this holiday season.
[Read]

As mentioned in the article, Modern Warfare 2 is highly anticipated and goes on sale in November with enough lead time on Christmas to sell big.
You’ll note it’s precursor is already #4 on the list and this time it’s a proven formula.
Question is will it sell enough in two months in a recession to fight and claw onto the list?
I think this is worth noting as well. GH3 was the first rythym game to ship with all 3 next-gen consoles supported and I know I hunted for that sold out sucker for the Wii for a few days before finding an unlikely copy at Blockbuster by sheer luck.
After that, the economy started to tank and the genre diversify, no doubt hindering concentrated sales of any one rythym game.
Well, for argument’s sake. I’ve bought GHIII twice because of the Les Paul. And both times, returned the game itself to a different store, because I have a) the game already, and b) no moral compass.