Facebook: Actually, there are 44 million active monthly users of our iPhone app, not 104 million

Yesterday, the internet collective noticed that Facebook was claiming some astonishing monthly active user figures on its respective app fan pages. At the time, Facebook was showing just over 100 million users of its Facebook for iPhone app, nearly 60 million BlackBerry users, and a bit more than 12 million using the Android client. These numbers have continued to rise in the face of contrarian evidence -- for example, how could there possibly be over 100M users of the iPhone app when only 100M iOS devices (a number that includes the iPod touch, iPhone, and iPad) have been sold as of June 2010? Easy, it all comes down to how you define "active." Here's the official word we just received from a Facebook spokesman:

"There are currently 44 million monthly active users of the Facebook for iPhone app. We recently changed the definition of mobile active users to exclude those who have only liked or commented on stream stories. Instead we are counting "active" users as people who have taken explicit actions within an application. This practice is more aligned with how we count overall active users for the site."

So yeah, not 104 million, but that revised number is still a significant proportion of all iPhones (59M iPhones as of last quarter by our calculations) and iPod touch devices (Apple doesn't break these numbers out) to have ever sold, let alone currently in use globally. Any wonder why Google and Foursquare are worried?