AT&T would not comment on this unlimited option, merely stating that "We handle customers and their situations individually, and we're not going to discuss specifics." Some customers were reportedly presented with this option when they called customer service and threatened to switch to Verizon. In these cases, this unlimited data option is not an unadvertised loophole but the standard practice of offering customers extra benefits when they try to cancel their service.
AT&T may also be rewarding faithful customers by resurrecting this plan on a case-by-case basis. Verizon confirmed yesterday that it will offer the iPhone 4 with an unlimited data plan for $30 per month, AT&T would not want to lose long-term customers to a competitor's unlimited plan, especially when that rival is Verizon.
Regardless of the reason, a growing number of individuals are reporting they have been able to switch back to an unlimited plan. If you may be eligible for this switch, take a few minutes to contact AT&T and see what happens.