The details on the so-called adventure update for Minecraft, vague as they are, were well received. This was originally planned to be the 1.7 update, but that content is now being rolled into 1.8.
"Me and Jens have been independently working on stuff for the adventure update," writes Markus Persson, "and it’s been growing in scope as we’ve been working on it. That means it will take quite some time to finish, but that it will hopefully change the game a lot to the better."
As such, 1.7 will see a release "soon" -- look for pistons and "probably a couple of bug fixes." Drat!