The question remains, will Apple keep using 15W chips and make a rMBP12, or will Apple experiment with the ultra-low power Broadwell and preparing for better future generations, now that Core M chips are able to deliver minimal performances but not being able to sustain heavy load as the price to remain cool, to make a rMBA12.
Btw, this Samsung laptop will be on shelves some time in Q1'15, Apples never shows you what's in labs, and make products announcement when close or ready to ship (iPhone, nMP, aWatch, etc are counter-examples of course). So technically, you can't yet say Samsung has released a fanless 12" laptop with a retina screen before Apple.
Interesting laptop, would like to see it tested on thermal and power consumption vs perfs, to see how Samsung handles the fanless design. Ativ might stand for "Always throttling impedes vaporization".