Yes, you read that right. 600,000. According to a press release from AT&T, that figure is more than 10 times the amount of 3GS iPhones sold on the first day last year.
That huge number, though, does bring some disappointing news along with it. From the release:
Given this unprecedented demand and our current expectations for our iPhone 4 inventory levels when the device is availableJune 24, we’re suspending pre-ordering today in order to fulfill the orders we’ve already received.
This shipping delay has to raise the question of whether the troubles from yesterday caused some further unexpected issues. Regardless, the phone is doing leaps and bounds above even the gigantic estimates that were first predicted.