Many of the stats we have about iOS marketshare and demographics come from third-party companies, most of whom are tracking ad impressions within their network. As such, their stats have the potential of being inaccurate, and need to be taken with at least a little bit of salt.
Looks like online ad network Chitika can be trusted though. Earlier this week, we reported that Chitika was now tracking 74.1% of all devices as running iOS 7. Now, Apple is backing those numbers up, and it makes Google look pathetic.