I read on News.com that Google is promoting a new attribute for the html tag <A> for preventing comment spam.
Example: Visit my <a href=”http://www.example.com/” rel="nofollow">discount pharmaceuticals</a> site.
Google will not follow such a link (because of the nofollow attribute) and hence the linked site will not get Pagerank. This should give less incentives to blogspammers in automatically commenting your blog with spam messagges. I think it will not work but this is just a try for tacking spam and hence worthwhile.
What is more interesting is the “decentralized” evolution of (HTML) language. The new attribute is just a proposal from Google to extend a standard language but Google has a so high reputation that many people will follow this suggestion and this means Google has the power to change HTML language. Technorati did something similar proposing rel="tag"
just few days ago. Technorati proposed also VoteLink with rel="vote-for"
and rel="vote-against"
and XFN with rel="friend met"
and others relationships-related tags.
Actually everyone can propose a change in HTML language (or whatever language/protocol) but it is of course difficult to have it accepted by a significant number of players/content creators.
It will also be interesting to see if this language evolution will produce different linking behaviours.
Yeah, the google proposal is quite obscure. XFN is actually quite old, and indipendent from technorati.
Indeed, the semantic web concept is turning more and more into a social tool rather than a geeky toy :)