The data seems pretty clear. Prior to June 8th we have a fairly low adoption rate of ~3%. Starting on June 9 this jumps up to 6-8%, which can be directly tracked to the developer release at WWDC. Starting on June 17th we get a huge jump as all the non devs start upgrading. We’re currently running at an overall 75% upgrade rate which is pretty insane considering the number of devices and the fact that its only been 5 days.

Overall Upgrade Rates

This graph adds up both the iPhone and iPod devices and just measures overall upgrade rate for both devices.

iPhone Upgrade Rate

Given how many more iPhone devices there are vs iPod Touches it isn’t very surprising that this graph looks fairly similar to the Overall graph. The iPhone upgrade rate is a bit higher then the overall rate, currently sitting at 79%.

iPod Touch Upgrade Rate

This is somewhat more interesting and shows the impact of that annoying $10 fee that Apple charges for upgrades. While the iPhone upgrade is almost 80% the iPod Touch has just passed 50%.