You can see the original suggestion and give support on minecraftforum.net!
For those unfamiliar with the concept, this would mean:
- An over-all reduction in lag.
- Possibility for infinite world height and depth.
- "Severe crippling" of X-Ray hacks in multiplayer (ONLY in multiplayer)
- Reduction of overhead on both client and server.
- Increased maximum size of redstone projects.
- The possibility of three-dimensional biomes.
- Potential for much larger and more realistic terrain.
UPDATE (08/21/2013): The Cubic Chunks suggestion is still gaining a lot of support and is currently at 1600+ supporters! But even so, it's still pretty unclear if Mojang has any intention of working on it yet.In the meantime, MCForums member Barteks2x is working on a revival of the original Cubic Chunks mod. His current version is very buggy and unavailable to the public, but looks promising:
If you want to keep updated with the suggestion your best bet is to keep up with the original post on minecraftforums.net. But I'll try to keep this article updated with anymore big news ^_^
Some pics taken from the old Cubic Chunks Mod: