Is Twitter and FaceBook a vialble source of traffic for all firms?

Fred Wilson, a partner at Union Square Partners, blogged today about the impact of social media on driving traffic to 3rd party sites. Specifically, Fred's post highlights the power of Twitter and FaceBook in driving traffic to websites. However, while the data certainly shows that firms should be using these outlets to drive traffic, can Twitter, FaceBook and other social mediums be leveraged by all firms?

In my case, it is not obvious given my firms brand (Harvard Business Publishing) and the restrictions surrounding the use of it for marketing purposes. Not only do the restrictions have to be weighed, but would Twitter and FaceBook have the same effect on driving traffic to our site?

Given the impact of Twitter and FaceBook, we will certainly look into having a presence and it will be interesting to see, brand restrictions aside, what the outcome will be if we do use these outlets.