4J Studios has announced that Minecraft: Xbox One Edition has been handed over to Microsoft for final testing. This suggests a release sometime in September, but as we saw earlier with the PS4 version, there's a chance it could fail. So let's keep our fingers crossed.
— 4J Studios (@4JStudios) August 29, 2014
Earlier this week, 4J was testing a small update for the Xbox 360 versio that will add the ability to transfer Xbox 360 saves to the Xbox One version ahead of its release.
On the PlayStation front, 4J also handed Minecraft: PS4 Edition over to Sony for what is also, hopefully, final testing. There's still "a bit more work" to do on the Vita version before they can submit it to Sony.
So should the Xbox One and PS4 versions both pass testing, there's a good chance next-gen gamers will be playing Minecraft some time in September.