For all the excitement about social media, there's a specter hanging over its use by companies. Is all this Tweeting, blogging and Facebooking paying off? For some proponents, the question is irrelevant. But for budget-strapped CMOs -- who, while eager to find new ways to reach consumers are under more pressure to prove their efforts are pushing the business forward -- measurement remains the single greatest challenge to social-media adoption. Here's what three marketers well-versed in social media are doing to measure their participation and justify new investments.
