Grass

Tall Grass is an upcoming feature in 1.6. It will spawn on Grass blocks in certain biomes. Seeds will no longer be able to be produced from grass blocks and will only spawn from harvesting these blocks. Little else is known about it however. Tall grass will not be a solid block, but rather an aesthetic weed that does not block movements, like Sugar Cane and Wheat; just in larger quantities.

The color of tall grass will be biome dependant, and the same color as grass.