Mobile search is going to be a big topic. And its not just a case of putting a mobile interface on to an existing web service. The mobile environment presents opportunities for intelligent search (location, environment, advertising etc) and also a number of challenges (keypad entry, screen size, display limits to results etc). yahoo and google have recently entered this space and 4Info and Caboodle are the new start-ups to watch.
14/07 - also Medio Systems
29/09 - "mobile operators fear the Google effect" - VNUNet
05/10 - JumpTap (similar UI to MotionBridge)