Boosted by a single month 5% increase in the use of OS7, and a 2% increase in the use of OS6, the percentage of users with a minimum OS of 5.0 has exceed 90% for the first time. Meanwhile the use of OS 7 is up to 7.7% after just two months, while last year it took OS6 4 months just to get to 7.2%.
This data was taken from downloads of the popular BlackBerry strategy game Pixelated. Data shown on the chart is from the beginning of September 2010 through the end of September 2011.

I would guess that the difference you are seeing is due to the fact that you are measuring ‘Paid Apps’ as opposed to free ones. An interesting difference.