Briefly, I've been playing with Ask's experimental new search interface currently called 'AskX'. Read/Write Web has plenty of information (though the interface has changed a little since that post was published). Innovation in the search interface is something I'm really interested in. Microsoft, with its Live branded image search has already been exploring this area and Ask appears to take things to the next level.
There are two fundamental areas of innovation in search - the back end, which Powerset is disrupting with its NLP technology, and the UI which companies like Ask are disrupting. The search giant Google, on the other hand, isn't innovating in either of these spaces, opting rather for a new application a week path.