Apple is unlikely to issue a press release however. Maybe, the 20th billion download, or the billionth paid sale might be significant enough to get Apple's PR core leaping into action. In general though, the App Store was designed to enable people to download stuff and that's exactly what it's doing.
Numbers, numbers
For the record, it took over nine months to do the first billion downloads, just over five months to do the next billion, three months for the next. The period between four and five billion downloads was around two months.
At the present - thanks perhaps to the Christmas spike - the tenth billion was completed in less than 45 days.
In contrast, it took iTunes seven years to do one billion downloads. It's not an apples-to-apples comparison of course, in terms of the ratio of free to paid downloads, or the numbers of devices available to each store, but demonstrative of the pace of change when it comes to digital distribution.
What's also interesting to note is that the number of apps available for download on the App Store is following the same rate of increase as this Wikipedia-sourced graph demonstrates. (The red line is the downloads, and the blue the number of apps.)
As for the ten billionth download, it was Paper Glider and purchased by Gail Davis of Orpington, Kent, UK. As the winner of the App Store Countdown to 10 Billion Apps, she receives a $10,000 iTunes Gift Card.
[source: Apple]
