A sure sign that the next-gen iPhone is approaching fast is retailers eagerly dropping prices on current-gen models. RadioShack, which has just had a week-long sale on the iPhone 4, has now further cut prices for all iPhone models currently in stock.
All models of the iPhone 4 now continue to get the $30 discount, which in the previous promotion had dropped the 16GB iPhone 4 from $199 to $169. On top of this, if you trade-in an iPhone 3G or 3GS, you can get as much as $150 towards the iPhone 4 purchase, bringing down the 16GB iPhone price to only $19 and the 32GB model to $119.
This promotion will continue until August 20, which suggests that the iPhone 5 may be hitting in the second week of September after all. Some recent rumors have pegged the iPhone 5 for an October release, but with such aggressive promotions in the month of August, October looks to be too far out.