Experience Orb

Experience orbs are a possible new item that might come out in beta 1.7. They might look like golden/yellow balls that could be dropped from enemies. The orb wasn't officially confirmed by Notch, but he did confirm that a hidden clue of something that will be added to beta 1.7 is in the picture of the new lighting and the blurred 1.7 change-list. It is believed by some to be this orb.

Possible proof for the inclusion of the orb
In the lighting system photo a small yellow spherical shape can be seen on the left side of the screen, but a day after the photo was published Notch claimed it had an "Error" and posted a new one, this time, without a yellow sphere. In a latter tweet, Notch showed a picture of a 1.7 change-list. Although it was completely blurred out and was, at first, thought of as a joke ,Notch stated that one of the pictures with the new lighting system and the change list had a secret in them. People all around the web started speculating. One place that people discussed it was on the Minecraft forums, where it was discovered that the tabs at the top of the change list that were partly covered, could be decoded. After successfully decoding it the tabs read: ExperienceOrb.java, changelist.txt, Level.java, Tile.java, HugeMushroomTile.jav(a?), HugeMushroomFeature.(java?), RandomLevelSource(cut) Therefore, it was dubbed that the yellow sphere might be an experience orb. As of now, Notch has neither confirmed nor denied this idea, but he did say that the answer was found.