Despite the fact solely MOTHER 2 (known to us as Earthbound) has been released outside of Japan, the MOTHER series has some immense popularity overseas from the single release. Shigesato Itoi has been more aware of this fact in recent years. As such, something is finally in the works.
From the way it's been worded, most people are assuming it'l be a re-release of some sort. Whether it's MOTHER 1 and/or 3 gettin' localized onto the Virtual Console, a full-blown remake on the 3DS/Wii U, or even a spin-off, no one yet knows. The fact that there's actual development goin' on for anythin' MOTHER-related is still a groundbreaking development either way.