Dan Olsen at BYU gave a talk, "Interactive Machine Learning", at UW CS a couple months back.
Dan's group is doing some clever work that combines machine learning and HCI. The UW CS talk is good but long. If you are short on time, first take a look at the fun short demo videos Dan's group produced.
I particularly recommend seeing the clever "Screen Crayons" (WMV) application for annotating documents and the "Teaching Robots to Drive" (WMV) demo of an intuitive interface for training a robot car. The "Image Processing with Crayons" (WMV) demo is also good for getting quick introduction to the core idea.