If you decide to wander into your local Apple Store with the intention of buying a few iPhones, you'll be pretty disappointed, as you are now limited to purchasing only two iPhones. That's not really going to affect a ton of people that are buying them for personal use. However, if you try to pay cash for your iPhone, you'll get quite a shock.
Apparently Apple is no longer accepting cash for iPhones. This move is speculated to be Apple's way of preventing people from purchasing the iPhone with the sole intention of hacking/unlocking it.
It's really no surprise that they don't want you unlocking one and using it on another network.. AT&T pays Apple something like $18 per month for each iPhone for the life of its two-year contract.
Apple Stores refuse cash iPhone buyers [via MyiTablet]