Is Edison a [Something] killer?

No, it's probably not.
Ever since the Edison broke into our lives, people keep comparing it to boards from the makers world - like Raspberry Pi and even to Arduino. I think it's a total miscomprehension of what this module is and what is its purpose.
Edison is not primarily targeted at makers. It is targeted at IoT manufacturers with medium-high manufacturing volume, that need some real computation power, which even high end microcontrollers can't offer, along with some serious connectivity.

Intel® Edison (Source)

Intel chose to introduce the module through the makers community, partnering with major names in this area such as Sparkfun. This is a tactical marketing move, and an obvious question arises - why? I can think of two reasons. The first one is that Intel truly believe that this is where innovation comes from. The second is that Intel does not want to lose another market segment to ARM, as it did with mobile platforms (cellular, tablets etc.), understanding that future engineers may prefer familiar technologies from their making days. On the way, it's trying to fix its absence from this small, but very loud market.
The true competition to the Edison will not come from Pi nor from Arduino - it will come, once again, from ARM with ultra-cheap, connectivity-centric modules such as HE and HLK-RM04. While not providing half as much computation power offered by Edison, they do allow both makers and manufacturers to enable product connectivity easily and on-the-cheap.