This happens both on my Windows 10 PC and on my surface pro 4 tablet. When opening most worlds (anything larger than a brand new world) there is significant lag in movement often and chunks load extremely slowly. This happened before the 1.1 update, but it's become MUCH more frequent afterward. The game is unplayable now: I can't explore because I spend much more time waiting for a chunk to load than I do exploring it, and I can't fight mobs (they can hit me repeatedly before I can even get in one swing because of the lag). Here is a link to a video that shows these problems: https://youtu.be/5iD2I7ICqZo