This news comes directly after Nintendo has begun to halt production of the NES Classic worldwide, following assurances from Nintendo of America and Japan that they wouldn't actually do that (and even still after Nintendo denied that the Wii U would be ceasing production, then subsequently did just that weeks later). There are also a few clues that back this up. For one, common sense, and another, the whole "Classics" brand of accessories that didn't necessarily state "NES Classic," but a general "Classic" line.
Nintendo is a weird company, so I fully expect this to actually be real, garner hype, sell well initially, then fizzle out. That's exactly what happened with the NES Classic at least -- stores got a pitiful allotment, scalpers rejoiced, and it was never restocked en masse.
Sources: Nintendo to launch SNES mini this year [Eurogamer]