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
