600,000 iPhone 4s pre-ordered, Apple apologizes for issues

We were amazed last night to see both Apple and AT&T sell out of iPhone 4 pre-order units despite the sustained ordering issues, and now we know why: Apple managed to move 600,000 iPhones in just a single day. Yes, that's a lot -- Apple says it's the largest number of pre-orders it's ever taken in one day, and AT&T says it's ten times as many orders as it took for the iPhone 3GS. It's not all sunshine and roses, though; Apple's also apologizing to the large numbers of people who simply couldn't get through yesterday, and AT&T's suspended pre-orders entirely until the device is in stock. We're guessing AT&T might also be putting the stopper on things while it gets those pesky security issues under control, but there's a chance the carrier is just trying to deal with the insane order volume coming from Apple's servers -- it served up 13 million eligibility checks yesterday, shattering the previous record by three times. All in all, it looks like Apple has a hot item on its hands here -- almost too hot to handle. Here's Apple's full statement:

Yesterday Apple and its carrier partners took pre-orders for more than 600,000 of Apple's new iPhone 4. It was the largest number of pre-orders Apple has ever taken in a single day and was far higher than we anticipated, resulting in many order and approval system malfunctions. Many customers were turned away or abandoned the process in frustration. We apologize to everyone who encountered difficulties, and hope that they will try again or visit an Apple or carrier store once the iPhone 4 is in stock.

Update: Looks like that "ships by" date just slipped once more from July 2nd to July 14th. Yikes.