Ordered mine this morning (round 8am est) and it has changed to a status of shipped as of 10:36pm this evening. I believe that if you had ordered last week, chances are they will overnight it to you so you receive it Friday from one of their many local shipping facilities.
Shipping from China will likely take until Friday hence why a lot of more recent orders are seeing changes.
No worries...I'm sure everyone will get their phones on time, Apple tends to know what they're doing.
Did you order via Apple's pre-order?
(FYI to others: As far as I know, pre-orders for AT&T made on/before the 13th* are on-time for Friday. For Apple, anyone can continue to order up until the 17th and they will arrive on Friday.)
*Thanks, KoNeko, for the correction.