Me thinks for the Smart phones to come of age and become a solid SEM platform ( these are my thoughts) we'll need to see Search engines moving to NLP natural language search. We have the infrastructure partially ready to annotate the web to make the web totally semantic. With hcards and microformats etc. But on the whole, web as of now is composed of unstructured HTML pages. NLP search engines ( essential meaning machine understandable language) permits complex query in sentences just like we would ask questions to a human being. There are already Haiku and powerset working on the same search methods.
But this i believe is a very crazy idea of mine and i think i should patent it.

it essentially marries the above ( NLP) with a unique way of triggering search - voice activated search. Why most mobile users don't do much search on net? most mobile devices for the sake of convenience have minimal type pad except a few handsets which come with a QWERTY type pad. Mobile search through text is slow and most mobile users would prefer a computer to do their search if they had one nearby.
It would be fantastic if i could voice search my query through a mobile phone and have the search engine deliver the results page to my handset.