I don't have a problem with a numbers game - but when I see things like this I say - em - who cares?  A billion users?  so what?  Now you tell me there are a billion active installs?  Or that a billion people have it installed on a device they use physically, now I start to care (but only if those are important numbers to whatever I'm trying to figure out).
But the fact that there are 1 billion plus users of Ubuntu, again - who cares?