Danny Sullivan created a new thread named Can Tagging Help Search? based on his recent blog entry at SEW blog named Tagging Not Likely The Killer Solution For Search. Google, Yahoo! and others have created this nofollow attribute which is not really part of the issue that Danny has. But in the Indexing Summit at SES NYC Tim Mayer from Yahoo! has brought up a possibility of allowing Webmasters to tag up their pages, to let the search engines know what are the various layout elements that construct the page.
This is all fine and good if people respect tagging. Maybe respect isn't the proper word, more like, if people do not abuse the tag. Most people are not of the opinion that tagging can make it back to determining relevancy, some feel it will have a limited affect. Either way, Danny is no supporter of this initiative. If it comes back, it won't last long, in my opinion.