I think this is a teaching that is growing quickly. There's nothing new about it, but it seems in the last couple of years it's proponents have spread like wildfire (pun implied). Much of the debate stems around the word in Greek aeion/s. The dispute centers around whether the word means eternity or a period of time. In the case that it's definition is just a period of time, then the idea that hell is a place of eternal judgement is dismissed.
My ultimate conclusion is that before anyone tries to read into what a Greek word means or doesn't mean so that they can make their own assumptions, they should approach a Greek (meaning actual Greek national) Bible scholar, knowledgeable in ancient and modern Greek, and yes, they're around. I find that people who continue to argue over the word and hence it's theological significance, are unwilling to take their query to a true expert. This produces predictable results.