According to Sharad Verma of Yahoo! look for they are progressing out some new features extra in their algorithm to rank websites in after those coming days. SO be complete to see a few changes in your yahoo rankings.

Advantage of Yahoo announces hold for X robot tags in http headers for no index, noindex, nofollow and nosnippet functions. Previously you can use these tags within html only except from now on you be able to use it in http header which gives you more flexibility to attain exclusions on PDF, Word papers, PowerPoint, video and other file types counting html files. Here are some examples of using X robot Tags given by yahoo:

* X-Robots-Tag: NOINDEX -- If you don't want to show the URL in the Yahoo! look for results.

Note: We'll still need to move gradually the page to see and apply the tag, so if you don't wish to have the page crawled, use robots prohibit on robots.txt.

* X-Robots-Tag: NOARCHIVE -- If you don't want to show cache link in the explore results page.

* X-Robots-Tag: NOSNIPPET -- If you don't want to display review in the search results of that page.

* X-Robots-Tag: NOFOLLOW -- If you don't feel like Yahoo! to crawl links in the page.