[Lots of interesting data][link]. As [a commenter notes][comment], the “ratings” metric should be taken with a grain of salt. Instead of defaulting to “no” stars (and possibly prompting the user to choose a rating if they’ve not done so) the App Store defaults to 1 star. Since it doesn’t require you to select a star, there are a lot of positive-to-middling reviews with 1 star ratings.
[link]: http://radar.oreilly.com/2009/04/itunes-app-store-billionth-download.html “Waiting for the Billionth Download – O’Reilly Radar”
[comment]: http://radar.oreilly.com/2009/04/itunes-app-store-billionth-download.html#comment-2057634 “Commenter”