I have noticed that whilst having a look at the latest snapshot and looking through the new types of arrows, I noticed that the tips of the arrows are completely black where they should be the respective color of what potion effect that the arrow gave off. I also noticed that some, but not all of the potions still had the enchanted effect on them but underneath that they where also completely black e.g. Regeneration which is usually pink and swiftness which is usually light blue.

The arrows and the potions still give off the appropriate effect so I am just amusing that it is a error with the potion overlay texture.