Yes, there is a great need for these services. Unfortunately, many companies are still in the mind-set that online marketing at all is a small line-item, not a major pillar of a sales and marketing program.
The largest growing segments on the Web are anything with “social” attached to it. Anyone with Web access can now be perceived as an expert on your product, whether or not they deserve those credentials. On the other hand, many companies just try to wing it as far as SNM is concerned, instead of piecing together their own coherent web of influence, encompassing user-submitted reviews and videos, company/public discussions, and footprints where their current & potential customers are.
The largest hurdle in this, especially for organizations that grew up in the print media & trade show mind-set, is the educational aspect. This explains why it’s important, and why the market (and most likely their competitors) are moving this way.