Given the option, would you like to search the web using your voice? Google may be prepping just such an endeavor, with an application for the iPhone that'll let people surf, or at least search, by using voice commands. The application would put them on more equal terms with Microsoft and Yahoo who already have similar tools.
No matter when it appears, it'll probably be only a short time before it makes the migration over to Android-based phones as well. With video email chat already in the works it could be that Google has hopes to change smartphones into much different tools that what they are now in a relatively short time. Then again, there are a lot of search terms that we'd want people to just continue to type in not all search terms are G-rated, after all.