As of a few minutes ago, with some intermittent switching back to the original date and variation among different areas of the country, the US Apple Store website is now showing a pretty consistent July 2nd
Despite some near-catastrophic systems issues during the day for Apple and AT&T, and some breathtaking account security problems on AT&T's upgrade pages (users seeing the wrong account when they log in to your site is never good), it seems like the infrastructure held together enough to work through a huge surge of business today.
We won't know for sure how many iPhones were preordered today until & unless Apple and AT&T choose to share, but it's easy to say 'millions' with a straight face.
Speaking of poor estimation skills... remember when I said that the iPhone 4 was unlikely to see delivery dates bumped on the first day of preorders? Uh, yeah, sorry about that. If Joe Wilcox can admit (in grudging, snarky fashion) that he was wrong, so can I.