I'm actually quite amazed by the adoption rate of iOS. Before iOS 5.0, it was very very hard for users to upgrade their OS. Android on the other hand is supposed to be easier to upgrade.

There was some statistics last year that shows only 50% of iOS users sync their iOS devices regularly, which means those people went out of their way to go and get the OS update. I still can't believe this fact.

Now that iOS does update over the air, of course more iOS users will update quicker. Especially when the update comes straight from Apple, but the fact that iOS users upgrade their OS very quickly before 5.0 still impressed me.