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I received that email 12 hours after pre-ordering when mine initially said 2 weeks. At this point, if you haven't received an email, it's probably safe to say you're in the 2 week batch.
 
It's all estimates for the first batch with an emphasis on guaranteeing those who are initially promised a delivery on Sept. 21, in fact get them that day.

By estimates I mean Apple has to take delivery from china first, and in turn distribute the phones accordingly to be processed. China says X amount are promised on a certain date and may indeed ship less or more.
 
I still have the Oct 5th ship date :( ordered at 4AM PST... I'm either going to try preordering one at my local Radioshack, or I'll see how many my AT&T will be getting and stop by after school. I'm sure they'd be sold out by then though.
 
Anyone who has experienced otherwise feel free to correct me, but from what I experienced and have seen, those emails only went out to those of us that had the "reservation" due to carrier servers being down then when we completed our orders got the two week date. Because the phone was indeed reserved the two week shipping was wrong and so they corrected it. I don't think anyone outside of one reservation people got the email correcting the shipping date.
 
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