A link is more a pointer than a vote, and that's why the nofollow attribute has been so controversial. Since search engines determine the importance of a page by indexing how many other sites link back to it. Now that Google is pushing the nofollow attribute on paid links and Wikipedia has implemented it across the board, the world of SEO is undergoing a dramatical shift.

Consequently, it is little surprise that SEO pundits are weighing in against the issue. In a recent post, however, Carsten Cumbrowkist at Search Engine Journal makes some interesting points about the multi-faceted nature of links. Since links are more than just endorsements, Cumbrowski's observations really emphasize the question of whether it is reasonable for Google to even try to determine the relevancy of the links. Cumbrowski writes:

Everybody talks about that a link is a positive vote for another web page by the webmaster who adds the link to his site.

[...] People also link to pages and sites they complain about [...] the people that don’t know about [SEO] link to the site they rant about to make sure that the reader is perfectly clear about who and what they are complaining about.

A better word for a link is “pointer” and not “vote”. Imagine that no search engines exists and think about what a link would be good for and what all links have in common. They have in common that they are relevant to the context they are being placed in.
[...]
Relevance does not mean recommendation. ,...]

The “Vote” or recommendation (which can be the recommendation NOT to use a service or buy a product) is completely independent from the link.
[...]
There are also the cases of a neutral point of view. A link would not be a vote about the product or service at all, but a simple pointer that makes aware of its existence, no more and no less.

Indeed, Cumbrowski's points are succinct. A link can serve many purposes, especially in the age of the blog. In the informational context of a blog, links are more about transparency and accountability than vote. All this raises some interesting questions of what the internet itself it. Is it primarily an economy or a medium?

If we decide that it's more of a medium than a message, then perhaps we should be re-evaluating how search engines work altogether. If they are going to persist in using links as a key indicator of page importance, then can they be trusted to pass fair judgement on whether bloggers and webmasters are using appropriate attributes when they link to another page?

The nofollow attribute was fully implemented at Wikipedia as of January 21st. As Cumbrowski explained then:

As of now are all outbound links from the english Wikipedia Site using the NOFOLLOW attribute, no exceptions.

No matter where you place it, Article Page, Talk Page, User Page, Project Page, whatever. No Link will get any credit at the major search engines.