Just in case anyone is interested, I found this page that contains the Top 25 Live games:
Top 25 Xbox Live Games Worldwide
You know what’s been spinning in your Xbox—how does it compare to what the rest of the Xbox Live™ community has been playing? These are the top 25 Xbox Live games based on the number of gamers playing ‘em. This list will be updated weekly, so check back each week to see what’s hot.
I find it interesting that Fable is listed at number 2 this week. :)