Paul Haddad from Tapbots let us know just how fast he's seeing users update to iPhone 3.0. Based on the headers included when their app Convertbot checks with its servers to get the latest currency information, Paul figures:
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.
Outside enthusiasts who regularly follow the news, users are only alerted to updates when they tether their iPhone to iTunes to sync. Looks like a lot of people are either enthusiastic enough to know about the update and want it, or fairly regular about syncing with iTunes.
Either way, these uptake levels are amazing.