Hello! Nice to Meet you. I wonder what attracted you to this post, but I can asure you, what you learn here will most likely interest you. 

My name is Colin (colin350), and I wrote a basic post about 5 months ago prior to the release of 1.7 discussing its advantages and drawbacks. The article was more about the discussion in the comments, but also getting people from all around to collaborate on a common topic. What I plan on doing with this post is besides giving you more detailed information besides the basic changelog, I want any readers to comment and possibly give their input (this includes questioning my opinions if you would like). 

---[Main Issues with 1.7]---

1.7 was a huge change for Minecraft, but mainly servers running Bukkit/Spigot. This includes the 100k + lines of code that mojang decided to change. This 'change' was what caused the lack of mods being updated, but also bukkit's slowness to release a stable and bug free version of Craftbukkit 1.7. In fact, the reccomened build is still 1.6.4. Beta builds still have bugs and glitches, and development builds really only allow the client on 1.7.8 to join the server. Plugins are also a hastle to create, as these lines that bukkit had to modify, we also need to modify those lines as well (I am a developer). Now what we can expect is that everyone will switch to 1.8 once it comes out, and servers will be full of bugs, and most likely the new additions won't work on multiplayer until there is a stable build for 1.8. Yet the stable build for 1.7 is still being worked on and it hasn't came out yet!

---[General Additions Discussion]---

Splash, just Splash.
Well for one thing, I am positive you have no idea what 'Splash' is without looking it up. To be honest, I just learned what it was 5 minutes ago. Well Splash is that changing yellow text on the title screen. Sometimes there is some witty quotes, and sometime it is just pointless and useless information that no one will ever care about. But, I promised the additions:

"That's Numberwang!"
"pls rt"
"Do you want to join my server?"
"Put a little fence around it!"
"Throw a blanket over it!"
"One day, somewhere in the future, my work will be quoted!"
"Now with additional stuff!"
"Extra things!"
"Yay, puppies for everyone!"
"So sweet, like a nice bon bon!"
"Popping tags!"
"OpenGL 1.2!" changed to "OpenGL 2.1 (if supported)!"

:o Difficulty!?!?! 
There has never been a significant difficulty change since Beta. Oh good ol' beta <3. Well news for everyone, especially server owners, difficulty will now be perworld. I guess people have a temptation to change the difficulty, because the changelog now says it will prevent the temptation. Mojang said they will still keep the /difficulty command.

Super Secret Settings?
Probably the one thing everyone did when 1.7 came out was to screw with the super secret settings, which generically was an over complicated way of saying 'shaders'. Well, mojang decided to add to this collection of shaders by changing the player's point of view. LvL Up! You are now a Creeper or Spider! Yeah so your skin changes and you get health boosts and abilities and stuff.... Now you are like: Awesomeee. Well I lied to you. You get either green tinted view, or octuple view. 

But if you read closely, it implies that you can spectate another mob, so that means you can essentially F5 a creeper :o. HAXX

Pff Achievements:
Well all I can say is, you will get a useless achievement if you craft a golden apple. Achievement intitled 'Overpowered'. Now what I consider overpowered would be a diamond apple. :3 

---[Gameplay]---

'@e'
A huge complaint with 1.7 was command blocks. I mean yes, they added useful commands especially for mapmaking, but it was still lacking something. Well I think mojang found all the clues and now command blocks can target entities! You can change the entity, tp them, and kill them. 

Commands :D
No need for NBTeditor anymore as you can now edit data through the command of '/blockdata'. '/clone' lets you essentially //stack blocks. '/execute' will let you only kill a certain entity grouping. The world edit copiers: '/fill'. '/particle': you will just have to find out! '/testforblocks', and '/trigger'.

NBT Tags :o
CanDestroy
Mostly for use in adventure mode
Items with this tag display the names of the blocks that they can destroy in the item tooltip
Example: /give @p minecraft:diamond_shovel 1 0 {CanDestroy:["minecraft:sand","minecraft:grass"]} to give a diamond shovel that can break grass and sand)

CanPlaceOn
Allows placing of certain blocks against other blocks in adventure mode
Example: /give @p minecraft:stone 16 0 {CanPlaceOn:["minecraft:diamond_block"]}

HideFlags
Allows hiding of certain parts of the tooltip
Bit field determining which parts of the tooltip to hide on an item. 1 for ench, 2 for AttributeModifiers, 4 for Unbreakable, 8 for CanDestroy, 16 for CanPlaceOn, and 32 for various other information (including potion effects, StoredEnchantments, written book generation and author, Explosion, and Fireworks).
Examples: Setting bit field to 3 would hide both ench and AttributeModifiers tags, and setting to 63 would hide everything.

PickupDelay
The number of ticks before an item entity can be picked up.
Set to 32767 for items that can't be picked up

ShowParticles
Option to show or hide all particles for a potion effect, while the 'Ambient' tag only shows fewer particles. Set to 1 to show, 0 to hide.

Lock:"Secret"
A way to lock containers from being opened using NBT tags
Mostly useful for adventure maps in adventure mode
Containers can be unlocked by clearing their string for Lock
Locked containers can only be opened while holding anything renamed to the given string, item is not removed on use[5]
The lock can be completely removed utilizing the command /blockdata

BlockEntityTag
BlockItem instances can now hold a custom NBT tag that is merged into a block entity when it’s placed
Example: /give @p command_block 1 0 {BlockEntityTag:{Command:"/setblock ~ ~ ~ minecraft:diamond_block"}}

rewardExp
Controls villagers giving xp for trading, set to true or false

Gamerules? Well I guess that will be a surprise. The changelog provides significant information on the gamerules topic. 

---[World Generation]---

Block Types Generation. Granite, andesite and diorite generate in pockets within stone terrain.

---[Blocks & Items]---

Diorite
Crafting recipe: 2 cobblestone and 2 Nether quartz in a checker board pattern
Can be crafted into polished diorite

Andesite
Crafting recipe: 1 cobblestone and 1 diorite
Can be crafted into polished andesite

Granite
Crafting recipe: 1 Nether quartz and 1 diorite
Can be crafted into polished granite

Polished Diorite
Crafting recipe: 4 diorite in a 2x2 configuration

Polished Andesite
Crafting recipe: 4 andesite in a 2x2 configuration
Polished Granite
Crafting recipe: 4 granite in a 2x2 configuration

Slime Block
Players and mobs that land on their top side will bounce, like on a trampoline
Bounce rebound velocity is scaled by impact velocity, can reach up to 60%
Currently does not affect item entities
Prevents fall damage
Walking on it is slower than walking on soul sand, close to one's speed whilst sneaking
Crafting recipe: 9 slime balls
Can be crafted back into 9 slime balls

Barrier
Acts like a full block but is completely transparent
Can transfer redstone signals and allows blocks to be placed on it
Can only be destroyed in Creative mode
Can be obtained using /give @p minecraft:barrier
Uses Block of Redstone texture for breaking particles
Becomes visible when a player in Creative mode is holding a barrier in their hand
Appears to be rendered as particles; always facing the player and become transparent when in front of nether portals

Iron Trapdoor
Can only be opened and closed using redstone, similar to an iron door
Crafting recipe: iron ingots in a 2x2 pattern, yields one iron trapdoor. Does trap doors doe.

---[Entities]---

Love those pointless and annoying creatures that guard end portals? Do you like the ones that take apart your build block by block and teleport away? Well guess what, I guess they are making a cross between these two entities. Its called the 'Endermite'. Oh, just wonderful >.>

---[Significant Changes]---

Goodbye block ids, welcome moar words .... 
I love it when they screw with F3
I thought Chat wasn't an issue?....
Animation? more like haxx. 
Want moar money eh mojang? Yeah Minecraft Realms needs a better name, it sounds just as cheesy as DaddyCheese hosting. 
3D Skins? But Mommmmm I wanted 4D ;(
Yes like I have a need for 64 doors at one time...
And More!


Probably should have avoided writing this late at night. Not like its 1am or anything, and its almost '5 o'clock in the morning'. Well these significant changes make up a lot of the drawbacks. Unfortunately, I will not discuss the advantages and draw backs in the post, as I want all of you readers to comment below and share as a group what additions are good, and what are bad. I basically just talked about my opinions and how I read a changelog. 

Thanks for Reading:) Means a lot. If you want more added, please either PM me or just simply comment. (Its late at night @.@). 

colin350

Diamond? Tell me if you liked it :D. Thanks for reading.