These are the planned changes for Minecraft 1.3. The expected release date is unconfirmed, but it should be released in the near future.
Personally, I'm most excited about the following editions:
- New slabs of the 3 new plank types.
- Wood slabs behave as wood, not as stone.
- Cocoa Plants that generate on the sides of jungle trees, which can be harvested for cocoa.
- Cocoa Beans have a new texture.
- Cocoa Beans drop from jungle tree leaves at the same rate as apples.
- Villagers spawned from spawning eggs will get a random profession.
- Wooden tools can be burned in furnaces.
- Large Biomes world type.[1]
- Fix for glitchy mob prediction in multiplayer.[2][3]
- Large amount of internal changes.[4]
- Silk Touch will be able to pick up Ice and Glass Panes.[5]
- Stackable items now stack outside inventory when thrown to the ground individually.
- Easier item manipulation within inventory
- Brewing Stands allow use of shift clicking to put items in it.
- [background=rgb(240, 236, 232)]? Shift[/background]+clicking can now be used to wear armor.
- Dispensers can place Minecarts on rails and Boats in water.
- Creative Mode updates
- While in Creative Mode, players can supply a powered minecart with fuel by right clicking it as if they were holding coal.
- Flying in Creative Mode is no longer affected by water and lava.
- [background=rgb(240, 236, 232)]? Shift[/background]-clicking in Creative improved.
- Potions will be in the creative inventory screen.[6]
- Improved creative inventory screen.
- Category Tabs and Searching
- Survival Inventory Tab
- Backpack inventory, 2x2 crafting grid, armor, and deletion box.
- Commands in Singleplayer.[7]
- Optional bonus chests placed close to the player when creating a new world.[7]
- Demo mode playable through non-premium Minecraft.net accounts.[7]
- Different crafting recipe for books.
- Added Book and Quill and Written Book.
- Ability to write in Book and Quill (up to 50 pages), save them to edit later, and sign them and title them to finish off the book.
- All multiplayer sounds have been fixed.[8][9][10][11]
- Fishing lines are now visible in SMP.[10][12]
- Hardcore in multiplayer (HMP).[13]
- Better chunk loading in SMP.[14]
- Singleplayer will be a local server.[15]
- Specific names for different Wood, Wooden Planks, Leaves, Saplings, Sandstone, Stone Bricks, and Monster Eggs. (e.g. Oak Wood, Birch Plank, Spruce Leaves, Jungle Sapling, Smooth Sandstone, Chiseled Stone Bricks, Stone Monster Egg).[1]
- Empty Buckets are now stackable up to 16.[16][17]
- Trading with Villagers.[18]
- Added Emerald
- Added Emerald Ore.
- Added Block of Emerald[19].
- Added Bottle o' Enchanting to survival mode.
- Added Chainmail Armor to survival mode.
- New Gravel texture.
- Arrows warping upwards in multiplayer fixed.
- Added Ender Chest.
- Villages spawned in Desert Biomes now have a different style.
- A new type of Golden Apple[20]. with attributes the Golden Apple had before 1.1[21].
- Stars are slightly smaller and slightly brighter[22].
- Added Sandstone Stairs.
- Added Tripwire Hooks.[23][24]
- Dispensers will eject water and lava source blocks (from buckets).
- Will also take water and lava source blocks if there is an empty bucket inside.
- Added Pyramids, a new structure in Desert biomes.
- Added Adventure Mode. [27]
- Added Jungle Temple.
- XP levels now increases linearly with XP (about 17 XP per level) instead of quadratically
- XP orbs can now be gained through mining ores, and using a furnace for smelting.
- Enchantment has been reorganized so the higher/stronger level enchantment is on the bottom while the lowest is on the top. (The middle obviously being in the middle of the enchantment table.)
- Maximum level for enchanting is 30.
- Using buckets filled with lava no longer consume the bucket when smelting items.
Source: http://www.minecraftwiki.net/wiki/Upcoming_features[/SIZE]
Personally, I'm most excited about the following editions:
- Emerald ore
- Trading with villages
- Commands in single-player
- Local servers for single-player
- Pyramids
- Adventure mode
- Jungle temples