Like others in the trade-in business, Scarsella has linked the quote volume increases to a much higher level of interest in purchasing the new iPhone 5 than shown prior to the iPhone 4S on-sale date in October 2011. He stuck to that reasoning today.

Thirty-five percent of the trade-in quotes produced on Wednesday by Gazelle were of various models of the iPhone 4S, which for U.S. consumers meant that they were expecting to pay as much as $849 for the new smartphone.

"Some of these are people who are willing to pay full price for the iPhone 5," Scarsella observed. Those consumers were hoping to use what they earn from the sale of their iPhone 4S to subsidize the full-price purchase of an iPhone 5.

Another possible trend gleaned from Gazelle's data, said Scarsella, was a move away from AT&T: 85% of the iPhone quotes generated yesterday were tied to that U.S. carrier.

The iPhone 5 is the first Apple smartphone to support LTE. In the U.S. Verizon has a huge lead over AT&T in the number of markets where it offers the faster data network.