If you notice this screen, adding 3G a la carte to the iPad is all or nothing. Either your account will automatically debit itself monthly for 250MB – or unlimited – or you’ll have to cancel the account and re-enter your information. It’s a pretty dire choice.
We have more images from the 3G set-up over at the original unboxing.
To be clear, the only apparent way to prevent AT&T from charging you again after the 30 days are up is to delete your account on or before your renewal date. I didn’t test it, but presumably you have to re-enter your information when you request another unlimited or 250MB month. In this way it isn’t truly a la carte in that you can’t “suspend” the renewal process until you’re ready for another dose of data. It does allow you to add international roaming packages, though, which is sweet.
A note just came from AT&T:
Saw in your post you were talking about having to re-enter all of your info if you cancel your iPad data plan. Here’s a bit of info – remember, these plans are pre-paid with no contract, so if someone decides to cancel, they can do it at any time. When they go to re-start a plan, some information will be stored to make the second time around easier, but you’ll need to select your new data plan of choice and update any other changes as necessary. Same as when you first established service, you’ll be able to verify all information before submitting…