Microsoft has a better attach rate for the most part because it came out first and because its most core audience are shooter fans. These fans go out buy all the Halo's, Call of Duty and Gears of War games they can. Also because the system has been out longer. 84 million more games sold despite launching a year earlier. Based on the same time frame Sony would be about 60 million ahead.
The systems are fairly similar with only 14 franchises on each system representing the consoles top 30 games sold. However, I am giving Sony the edge based on more exclusives.







