E-mail vs Blogs vs Social Media - which is offering the most e-commerce boost

[MktgRob]

As I work with a number of different clients who are using e-mail campaigns (through Constant Contact as well as their corporate e-mail), Blogging and social media enagagement (twitter, FB, youtube) to drive leads to their e-commerce sites, I am curious to know which ones work the best and in what industries these successes are being seen. If anyone would care to share their experience (good and bad) with any of these channels it would be appreciated. Please include the industries that you saw these results. Thanks.