Shigesato Itoi has updated his Japanese website noting that Mother 3 is still in development for the Game Boy Advance and should be released in 2006.
Mother 3 is the sequel to Mother 2, better known as Earthbound to Super Nintendo RPG devotees - a quirky and cultishly popular tale of suburban America, it was released in the US but never made it out over here.
Mother 3, meanwhile, was originally a Nintendo 64 title, and got some way into development on that platform, but never actually materialised.
Don't get to excited though - Itoi-san has gone on record before to discuss Mother 3's imminent arrival on GBA. That was in early 2003. Nintendo released Mother 1 and 2 as a GBA double in June of that year in Japan, but we never got hold of it in the West.
Hopefully this time Mother 3 will actually land, and then hop the oceans and do some business over here. Might be best not to hold your breath though.