Downloading worlds can delete other worlds.

Creating a new world and closing Minecraft will not save.

Soul sand and ice

Some blocks do not touch ground.

Minecarts stop on end of track.

Fireworks rockets are not shown in creative inventory.

Anvils can be broken by flowers.

Ice does not melt by torches.

Stairs do not connect properly.

Pigs do not react to carrots on sticks.

Floating signs

Painting can be placed on pollygonic blocks

Plants can still be destroyed by mobs.

Player is not always told when achievement is earned.

Piston still active when signal is broken

Torches on ground but not facing up

Pistons stay extended when using with redstone torches or daylight detectors.

Invisible mob barriers

Random sources of light

Clusters of blocks are seen as another block or not seen at all.