Google likes to use software to eat the world. But sometimes their software-only approach just ends up slobbering all over it. The point of Uber isn't the "sharing" of a ride, but the availability and predictability of getting one.
On the point of software eating the world google may be uniquely positioned to make something of this scale work- They have trend data for a majority of people with smartphones and I often see from Google Now cards that they know what I'll do generally before I have even decided. If used in the correct way it would deliver huge value and disrupt the established patterns of car ownership.
