Its also clear that the carrier wasn't ready for it. People with the original iPhone would get entire boxes mailed to them for their Cingular statement, itemizing every data transaction, but then all flat rate charged.
I had an original iPhone and did not get such statements. As I recall while Cingular was indeed not ready to handle unlimited data for customers, it wasn’t really a problem for the first iPhone since it wasn’t 3g. Once the 3g dropped , it was a problem since people were actually able to consume a large amount of data.