We are very familiar with the concept of separation of code from content. Yahoo recently tried to separate content itself into actual content and common content. What I mean is separating parts of a page that do not relate to the main content, such as navigation, menus repeated across the entire site, boilerplate text, or even advertising. Interesting!!!
Yahoo introduces a ‘robots-nocontent’ class which can be included with any HTML tag. By introducing this class within tag, the idea is to
• Focus on the main content
• Not to use those sections of the page marked for finding the page
• Improving abstract for the searched page by omitting unrelated info
How to use it?
<div class=”robots-nocontent”>Header of the site</div>
<span class=”robots-nocontent”>Navigation of the site</span>
<p class=”robots-nocontent”>Footer of the site </p>
My thoughts:
+ve
• Good way to segregate main/relevant content from general content
• More focus content
-ve
• Why “robots-nocontent”, why not “robot-content”?
• Is defining class a right approach? Most of the sites does not have well formed HTML, so think of a situation where you applied this class which covers the whole page content 
• Currently keyword density as well as its location is one of the prime SEO techniques. What will happen if websites start using this tagging?
• Is it not raising concerns with content security? Someone can define not viewable content within these tags and search engine will happily ignore this and show your site even in top sites 
• Need to be standardized before people start working towards it
What are your thoughts?