Mojang plans to release version 1.3 of Minecraft on August 1st. You can read the full details on what’s going to be added right here. (Spoiler: New ore! New blocks! Tripwires!)
Aside from new features, Mojang is also positioning the game for the release of their official modding API. Considering what the Minecraft community has already managed to do with the game, I can’t imagine what developers are going to accomplish once that happens.