Matt Peckham in his PC World blog today points to the DFC report published in Gamasutra about the prospects for each system.

He notes that Wii owners have bought 2.8 games per system so far, PS3 owners have bought 3.0 games per system, and Xbox 360 owners have bought 5.5 games. This appears to be accurate.

However, he dismisses DFCs note that this is not too bad for the Wii given its current software lineup. Instead, he calls the system a Gamecube with motion sesnors and essentially dismisses it as a fad. http://blogs.pcworld.com/gameon/archives/005579.html

He also ignores two things. First the system comes with a game, so people don't have to buy software upon hardware purchase. More importantly, if you annualize the figures (basically accounting for the Xbox 360s one year head start), they come out much differently. Wii owners buy 3.36 games on a yearly basis, still less than PS3 owners (3.6) but more than 360 owners (3.0).

Mike from Morgantown

Your math isn't quite accurate, given that not everyone bought the system at launch. However, I agree that some form of modification of the attach rate given that discrepancy is necessary.

it doesn't matter if wii sells less software. nitendo basically gets profit of 1.5 games for each console sold, which sony and Microsoft lose money on their console (360 does not break even right?)