I think here's where the difference would apply. Designers almost all of them use high resolution displays. And maybe Designer News is aimed at those designers, who're at the cutting edge.
Do you really think "almost all" designers use a specific model of a specific computer that shipped about six months ago? Hell, I consider myself a half-assed designer and won't upgrade to a retina MBP because a) the screens have issues b) the web has issues and c) most of the design software I use has issues.
Designing websites in a way that only works well on retina displays has to be one of the most ridiculous examples of the Silicon Valley bubble in recent memory.
