iPhone 4 reservations are different from pre-orders in that they weren’t pre-paid, and one’s iPhone 4 must be picked up at an Apple Store. If you used the Apple Store iPhone app to reserve an iPhone 4, you have just that, a reservation, and should receive an e-mail reminder similar to the one below.
We reported on Sunday that customers who pre-ordered their iPhone 4 began receiving shipping notifications, as well.
The header from Apple’s iPhone 4 Reservation Reminder e-mail