Earlier this month, AT&T effectively kneecapped the unlimited, no-contract data plan originally offered with the iPad 3G. They did, however, include a "grandfather clause" stating that if you'd gotten the unlimited plan before June 7th, you could still keep the unlimited plan as long as you wanted it.
"All fine and dandy," muttered a chorus of iPhone 3G/S users, "but what about us? What happens if we want to upgrade to the iPhone 4?"
No worries. Based on the above screencap from an iSmashPhone.com staffer, the same grandfather clause is in effect for iPhone data plans. If you already have it, you get to keep it. If not…well, they say nothing's more expensive than regret.