I just walked through the 3-step process to receive my $100 credit for being an early iPhone adopter. The process couldn’t be easier. You enter your phone number and serial number on the Apple web site, they SMS you an access code, you enter the code and receive the credit that you can use online or in person at an Apple Store.
I haven’t commented much about the early-adopter penalty. Maybe because I’ve been one for a long time. But I can’t ever remember receiving a credit because I bought technology on the first day it was available.