Yes, they've been on sale for only two months, but refurbished
While the $100 discount may be good news to wannabe iPhone owners with smaller budgets, it sparks a interesting question. Just where are the refurbished iPhones coming from? Is Apple getting enough returns so they can resell them at such a volume so soon after the phone's release? Or are Apple employees refusing their free iPhones? Or is this just a clever marketing ploy, the kind at which Apple excels? I bet on the latter.
Source: The Unofficial Apple Weblog