When Sawyer and Miles are talking about the benefit dinner, Miles ties his tie twice.
When Locke and Ben look down into the dark well in search for Desmond, the water surface ripples like the one of a lake disturbed by wind; the water was obviously inserted by CGI as it couldn't be lit properly and wouldn't have registered on camera. The next look into the well is by daylight and shows a flat, serene water surface.
Jacob says that Kate's name was crossed off the list when she became a mother. However, Jin and Sun became parents and their name wasn't crossed off.