I kind of felt the bolded was the case even before the 470 performance popped up. It seemed weird that shader efficiency per clock is around 15% worse with the newer architecture.
I'm still planning to get a 480 but it's a tough decision. 470 comes so close for a good chunk less, but I anticipate it being VRAM limited even at 1080p before too long. And we know so little about Vega, though with everything seemingly using HBM2 and 480 pricing, the cheapest card is probably going to be well outside my price range.
This is all Nvidia's fault, if they supported adaptive sync in monitors that didn't cost stupid amounts of money I'd just pick up a 1060.