Edit: Notch has clarified his intentions for the immediate future in blog-wise fashion:
Last week, I participated in the 7dfps and made a hectic shooter greatly inspired by Doom, called Shambles, and it was some of the most fun programming I’ve done in many months. This is what I want to do. I want to do smaller games that can fail. I want to experiment and develop and think and tinker and tweak.
Well, YOU follow Minecraft. Marcus “Notch” Persson, having moved on from Minecraft development a year back, has been focusing on an ambitious space sim 0x10c. Except, not any more. We knew that back in April Notch had put the game “on ice”, citing creative struggles. They don’t seem to have gone away, and now – as spotted by US Gamer – he’s told some people via a Team Fortress 2 livestream that he’s given up entirely. But some fans plan to make it anyway.