Google has released the results from a study on query suggestions for mobile search. The study tested search queries for phones with a numeric keypad. Typically, a 15 character query requires approximately 30 key presses to perform, according to the study.
But when query suggestions are added to the mix, workload and key presses declined while enjoyment increased. However, the suggestions did NOT decrease the amount of time spent querying a search.
Google has already implemented query suggestions for the iPhone.