Thanks for the information and links. My background is in video and image processing, well originally multiple target tracking, sensor management, and sensor fusion, but now I work in biometrics and video analytics. Understood about processing the information into a graph.

Your point about Google raises one of the obvious questions about this company... if Google is doing leading edge research in this field it seems unlikely they need to buy a "video search destination" site employing lesser technologies, that is unless it gets really really big (i.e. YouTube). They might be interested in some deep technology, but my impression from the reading I've done and the links you've posted is that Blinkx is using standard well known techniques to achieve their results.

FWIW: I was applying Markov modeling to areas such as mission planning and modeling integrated air defense networks back almost twenty years ago now. We didn't call them HMMs, but there were some very similar ideas employed.