I noticed while playing survival on the new snapshot that none of the leaves are rotting away and also random spires of dirt at times where there would be trees near the original spawn on survival mode. Like the leaves are destructible by hand and occasionally give twigs and such but they refuse to rot into nothing by themselves. 

to reporduce this bug 

1 make a new survival world with chest enabled

2 play it and cut down a tree

3 wait 5 minutes and not a single leaf will disappear after removing all surrounding logs.