Minecraft's creators have always been among the more talkative of game developers—Mojang's development process with Minecraft is nothing short of transparent.
Today, one of the game's developers, Nathan "Dinnerbone" Adams, stated their plans to include every old version of Minecraft into the new Minecraft client launcher, so players who want to play one of the game's older versions instead of its latest and greatest version can do so without having to go through the ordeal of having multiple installation directories for the game. Many modders run multiple versions of the game, for the sake of joining servers with incompatible versions or for testing out their mods.
@javifranciia We eventually will
— Nathan Adams (@Dinnerbone) April 24, 2013
In addition to the update regarding the client, Adams also stated that version 1.6 of Minecraft will add "quite a few new blocks" to the game. As for what those blocks are—he's not saying.
Version 1.6 of Minecraft will also bring with it horses, which game director Jens Bergernsten says will be considerably more difficult to obtain than pigs or any other trainable animal.
In addition to horses, usable equipment will now only be found in dungeons, to which Mojang has added even more chests. According to Bergernsten, chests will be located all over the place, including the Nether.
Horses in Minecraft will be considerably more hardcore to obtain. Equipment is now only found in dungeons, but we've added more chests too
— Jens Bergensten (@jeb_) April 26, 2013
Thankfully, these items will still remain craftable. The development simply provides players with more incentive to go dungeon delving in Minecraft.