In 1.3 we will be able to grow nether wart in the main world. Good bye nether, except for the ghasts.

Edit: and Blazes :)

 

Snapshot 12w27a is here! Let's jump straight into the info:
Boats, when broken, now drop boats
Re-added debug graph on F3 menu
Signs are stackable now: Crafting them now gives 3 signs instead of 1, stack up to 16
Added /debug command to enable and disable profiling
Changed a few things around pistons - Most contraptions still work fine, but some require changes to repeater delays and similar. Overall, pistons should have fewer bugs, but will appear to update slightly slower.
Improved performance on MP and SP, including reduced CPU, RAM & bandwidth requirements
When opening SP worlds, users are now given their local IP address & port instead of hostname & port to avoid OS conflicts
Creative mode inventory now shows potion effects
Fixed some bugs
Fixed /kill not working
Fixed powering specific glitched pistons crashing the game
Fixed a visual bug causing pistons to be partially invisible or in the wrong location momentarily
Fixed being able to place portals in the nether in locations where they would end up in illegal locations in the overworld
Fixed the game crashing when publishing SP worlds with certain language settings
Fixed players on minecarts, boats or pigs and spider jockeys not being displayed in the correct location
Fixed a bug with dispensers
Fixed /say not accepting some strings form the console, often triggering the help dialogue
Fixed being able to transmute blocks to certain data values using an orientation-dependant tripwire bug
Fixed drinking potions in creative not consuming the potions, but still giving empty bottles
Fixed signs sometimes not saving the text when placing them


You can download this week's Snapshot below:

Client: Download

Server: Download

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But...What About 1.3?

The 1.3 update has now officially received a target release date of August 1st, 2012! A week prior to releasing, Mojang plans to post a “release candidate” that is likely to be identical to the actual release. This version is intended to give server admins and modders a little more time to prepare for the new Minecraft version - of course, there is the benefit of players being able to test the client as well.

Minecraft 1.3 consists of a huge number of changes, and some of them are changes to the fundamental game engine. The most dramatic change is that they have kicked out single-player, and made it a shell on top of multi-player. There are two major benefits to this: first, it’s required for the modding api if we don’t want to have multiple implementations of every mod, and second, if bugs are fixed in single-player, the bug is definitively fixed in multi-player, too. Previously, bugs had to be fixed in both Single- and Multi-player.

Jens "Jeb" Bergensten had the following to say about the upcoming update:

Jeb said:
Minecraft 1.3: The Good

Lots and lots of bug fixes and new features. Players who mainly play in multi-player on servers should enjoy a smoother and more stable experience, as this has been our focus of the development. We’ve looked over the network packets and added encryption to prevent session stealing. Dinnerbone has updated the chatting screen, to allow for easier editing and clickable links.

The single/multi-player merge has added the possibility to share your single-player worlds with friends who are on the same local network. It has also enabled players to use multi-player-like commands in single-player (such as /gamemode and /give), but only if cheats are enabled.

We’ve added emeralds, emerald ore and a trading system that makes it possible to buy items from villagers. Villagers will add and remove items depending on what you buy.

We’ve added the possibility write in books and leave stories for other people.

We’ve added new terrain features, and you can choose to begin the game with a “bonus chest,” to get you started quicker.

We’ve added tripwire, so you can create new traps and contraptions.

We’ve also added new stairs, new half-slabs, cocoa plants and tweaked dispensers, leaves, cauldrons, levers, gravel, pressure plates, cookies, buckets, boats, minecarts, ice, furnaces… Plus you get magic orbs from mining and smelting (and not just killing monsters)!

Minecraft 1.3: The Bad

Since single-player has been turned into a shell on top of a background server, the game’s resource requirements have increased. When playing single-player, the game needs to be able to both simulate and emulate the world, which take many more CPU cycles. We’re working on optimizing rendering, but those improvements will not be included until Minecraft 1.4.

Minecraft 1.3: The Ugly

A couple of problems and expected features have been pushed to Minecraft 1.4. The most notable problem is the lighting issues causing black regions in the terrain. We’re looking into ways to solve this, but lighting is a very expensive calculation and we are struggling with finding a solution that doesn’t hurt framerate.

And the most notable missing feature is the modding API. Throwing out single-player was the first step in order to make the API possible, and that’s done now. We decided to release 1.3 without the API, because otherwise it would be an even longer wait for a Minecraft update.

We’ve also added an extremely basic version of “adventure mode.” We’ll work more on this in future updates.

To Summarize

The time between Minecraft 1.2.5 and 1.3 has been the longest update interval yet, and that was because we changed so much in the game engine. I (jeb_) was a little scared to push it to the public, but waiting even longer is not a solution.

If you want to get the whole Minecraft 1.3 change log, I suggest you read redstonehelper’s great summary here.