Oh, now doesn't this come as a surprise? The following is written inside EGM's "Rumor Mill" column in issue #216:
"Seems Disney and publisher Square Enix want to keep the Kingdom Hearts series beating -- hell, no surprise there. But this may be one: My mousy mole tipped me off that the next KH game won't be the third game in the series, but instead, it will be a spin-off that will appear on a hearty console. Don't worry, though -- KH3 will still happen...eventually."
To which console does hearty refers to, you ask? Well, none actually knows, but most of the NeoGAF community suggest it's either the Nintendo Wii or DS.