The SiteMap protocol created by Google has been used for year and a half, will now be embraced by Yahoo and Microsoft.
While Yahoo plans to adopt this effective Thursday, with the continuous support for its current protocol, Microsoft plans to terminate using its current protocol after it implements Sitemap Protocol in its search engine in early next year.
For more details check "Google, Yahoo and Microsoft partner to help webmasters"
Interesting and enlightening article on Viewstate.
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