Apple offers details on in-store credit to early iPhone owners
With early adopters upset over the drastic price cut on the iPhone on Sept. 5 (from US$599 to $399), Apple announced on Sept. 6 that it would offer every iPhone customer who purchased an iPhone from either Apple or AT&T, and who is not receiving a rebate or any other consideration, a US$100 store credit towards the purchase of any product at an Apple Retail Store or the Apple Online Store. Details are now online. Read more >>
NOTE: If you didn't activate your iPhone through AT&T, you won't get the rebate.
Looks like everyone that bypassed the registration process, by hacking for example, is SOL.