But you didn't include the blu ray sales
Those numbers are for top 10 only, here are the total software sales for the month:
"$159 million was spent on Xbox 360 games alone in January compared to $131 million on Wii and $80 million for PS3. (U.S. NPD, January)"
So it seems the blu-ray dudes actually play games too. With only 1/3 of the 360's user base PS3 users bought 50% of 360's software. Much better attach ratio IMO