I have found a number of bugs in the Nether with this latest snapshot. One glaring issue is the color of lava - It appears with a sickly green rather than its trademark orange. Another is how the lava blocks generate - They form an almost cave-like structure, with many lava blocks "floating" in the air without flowing at all. Lastly, the new Conduit block, which seems to place a water block upon use, allows water to be placed in the Nether without use of commands. I have proof in an attached screenshot.