Normally I don't play single player Survival, but today I did. I spawned a world with this snapshot and began to play.
I found two abnormalities.
1. Occasionally when I mined a block, it would go FLYING. I mean literally flying. Upon breaking the Item would launch across the cave up to about 10 blocks. Sometimes it would even glitch through the ceiling and into the tunnel above. (I would later be exploring new tunnels and come across an iron ore block floating on the ground.)
2. I noticed a texture change when breaking COBBLESTONE and MOSSY COBBLESTONE. The texture either looked: Normal. Or the break lines would HIGHLIGHT in DIFFERENT COLORS (Green and Yellow was the most noticeable.) Or the break lines would be PITCH BLACK and THICKER than normal. As I said I only noticed it on cobblestone and mossy cobblestone. It may do it for other blocks too, but I haven't noticed yet. I don't know if this is normal behavior for breaking certain blocks or not, as I rarely play Survival and usually stick to Creative.