Melon

Melons were introduced in Minecraft 1.8 Pre-Release, the Adventure Update.

Behavior
Melons will have a central stem that slowly grows until it reaches its maximum size, at which point the melon will randomly spawn a fruit next to it if the block below is Farmland. Melons will revert the farmland to dirt when it grows. Melon stems will grow more than one melon. If the central stem of the melon is destroyed, there is a chance that you will retrieve Melon Seeds.

If destroyed, melons will drop 3-7 slices, each will heal one food point. This will also happen when a Piston of any kind, pushes a melon block.

A melon slice can be crafted into a melon seed, to be planted as a new stem.

Crafting
Melon blocks can be crafted out of 9 Melon (Slice).

History
Melons were first revealed in an IGN interview with Notch.

On the Getsatisfaction.com complete ideas for the Ideas section, it has stated that Watermelons will be implemented.