The pricing change is just a price match by Apple, but both moves also serve as an admission by Apple and AT&T that sales of the iPhone 3GS GSM model will drop with a Verizon iPhone 4 out in the market. It is unlikely that Verizon will sell an iPhone 3GS version.
The practice of continuing to sell the prior year's model began with the introduction of the iPhone 3GS in 2009, when Apple continued to sell the iPhone 3G at a $99 price point, but with only 8GB of storage. When the iPhone 4 was launched, the "introductory" or "low cost" iPhone model was changed to the iPhone 3GS.
