Car owners have widely different affinities for social applications. Mazda, Honda, Pontiac, Hyundai, and Jeep have the most active customers; Ford, Nissan, Chevrolet, GMC, and Mercury have the least. Car brands should use these tendencies to plan strategy. For example, Honda owners are the most likely to react to online content, which the company could exploit with consumer ratings. No brand can ignore the social world; even among Mercury owners, the least active, half are connecting with social media.