I hoped for a "digital FM3a" for many years. I had ended buying the D600 before the Df appeared, but I probably wouldn't have bought the Df anyway - it was much too expensive, I preferred the 24MP sensor of the D600, and the Df overall design wasn't right for me - bulky compared the FM3a and an odd hybrid of manual controls on the top deck, but looks like a normal digital camera from behind. The low-end D600 AF module wasn't a big deal for me but I'm sure that put off some buyers too.
I'm sure Nikon could make the camera less bulky today and overall specifications would be much better, but even when it was released 4 years ago I think they could have done better, the price and specifications meant they missed a large segment of the potential market. So it is cheeky for them say we need to buy Df cameras before they consider making another...