Predicting target location given cursor speed and direction
Fitts's law gives you a guess for the length of the movement (in terms of screen distance), and so gives you a rough spot where the user is aiming. Make a list of "points of interest" where the user is likely to click (a priori), and then put together a score which takes into account both the probability that the movement ends at the point, and its prominence. Pick the point with maximal score.

Machine learning has been used to derive the parameters for Fitts's law, and I'm not sure anything more is needed here apart from some UI experiments.