I didn't want to highjack the other thread.
Here's my question - on the AT&T website it states: "Usage in excess of 250 MB for the 250 MB plan, or 2GB for 2GB plan, during any 30 day period to be billed at $14.99 for each additional 250 MB, and $10 for each additional 1 GB, respectively."
However, that option doesn't seem to be available. My only option when I run out of data (after expending the 2G plan) is to order another 2G for $25.
The website does also say: "Offer not available for on-tablet activation."
Does that mean you only have the extra 1G/$10 option if you ordered your ipad from AT&T?