It seems to me that although blogs and other means of publishing give people the opportunity, in theory, to express their views and concerns, especially ones of political value, very few people have that freedom in practice because of their employers.
Consider e.g. someone who works for a software company, is opposed to software patents and could speak from experience about their flaws…
Unions protect the interests of some workers as it relates to their terms of employment, but who protects the interests of employees as individuals entitled to engage in asserting their influence in a supposedly democratic environment?
Ok, some people would argue that you can always work elsewhere and even if not, you are still free to vote according to your own judgement, but considering that most people are not in a position in which they can choose where they work, this is yet another mechanism by which corporations and money have more influence than individuals. Effectively, lobbyists not only get to represent the interests of corporations, but speak on the behalf of all of their employees.
See also: Nick Denton: the First Blog Martyr