Minecrat 1.8 was finally released a month ago after a full year of being developed, and is currently the biggest and longest waited for update for Minecraft. It has a ton of new features, and a few rewrites of some parts of Minecraft, especially the inventory. Most new features are, however, are used by map makers. Map makers are usually people who make things like adventure worlds, or maps, or they make role-playing worlds. They distribute these for other players to use. Mods can usually do more, but the nice thing about these features being implemented into Minecraft is that it is now completely vanilla, so you don't even have to explain to a person how to install mods! Most of these features are used in command blocks, blocks which can run some new commands automatically when powered by redstone. It is very similar to programming. One such map that is quite impressive and uses a huge amount of the new 1.8 map making features is Planetary Confinement (I may do a blog post about it later, once I get around to playing it) by Samasaurus6. It is very similar to the Crash Landing modpack, except completely vanilla!
Some things you can do, and what this is mostly used for, are minigames. My favorite that I will probably try making it a lava rising game. You are in an undergound Dwarven City, and lava has started to rise from the void below. The object is to get as high as possible before the lava kills you. This will probably be multiplayer, if I ever finish/release it. How I make the lava rise is actually pretty simple. One popular 1.8 feature is the new /fill command. You can use that in command blocks to fill a large area. I have used it before for a lava rising parkour, but I had a problem with it then. The fill command can fill a pretty large area with lava (for example), and replace certain blocks only, but I did not want the lava to suddenly appear and fill the whole parkour room immediately. I wanted it to rise, and if the player wasn't fast enough he would get caught up in the lava. The problem was, for every block that went up, I needed another command block. A parkour room that went up 64 blocks would need 64 command blocks, which was a lot of copy and pasting. Only recently, I found a way that only needed a few command blocks.
Another popular 1.8 feature were armor stands. This may not seem like they could solve my problem in any way, but armor stands are used more in map making then they are used as a stand for armor. They have some unique tags you can put on them, to help with map making. You can make them so they have no gravity (they are entities, so they can fall normally). I can make a clock that keeps going around, and activating a command block that teleports the armor stand one block higher then whatever it is currently. Another great command that was added in 1.8 was the /execute command. You can use that on entities, to make them run commands as though the command block was there doing the command. This helps for setting blocks relative to an entities position. For example, if you wanted to make a cow spread ice wherever he walks, you now can. But what I use it for, is on an armor stand. Every time he goes up, I set a 100x100 block area in front of him into lava, replacing just air. This way, he keeps going up, and every time he goes up he sets an area to lava.
I noticed that when I was working with command blocks and armor stands, it seemed very similar to when I was programming turtles. This is just one of the many, many 1.8 features. I talk about a few in this episode of my podcast. It was done a while ago, however, but most of the features I talked of are added in the complete 1.8 version.