I have been having similar issues. It seems like the mobs are freezing on my screen, but they continue to move on another player's screen. My friends are having the same problems. In addition, I see hostile mobs "frozen in one location on my screen, but I can't strike them. Then those hostile mobs will attack me, but I can't see them attacking me. Many times, invisible Creepers have snuck up on me.
I have been having similar issues. It seems like the mobs are freezing on my screen, but they continue to move on another player's screen. My friends are having the same problems. In addition, I see hostile mobs "frozen in one location on my screen, but I can't strike them. Then those hostile mobs will attack me, but I can't see them attacking me. Many times, invisible Creepers have snuck up on me.