Susan Wojcicki on the Official Google blog:

One of the key ways that people find and access information on their mobile devices, just like on the desktop, is through search. As smart phones have proliferated, we’ve seen dramatic increases in mobile search volume. Over the past two years, Google’s mobile search volumes have grown more than fivefold, at an accelerated pace. In the first three months of 2010, people with smartphones with “full” WebKit browsers (such as the iPhones, Android devices and Palm Pre) searched 62 percent more than they did in the previous three months.