WebProNews

HighRankings.com's Jill Whalen broke some interesting news about tags webmasters can use to control how their content is shown in Google results. The information comes from Dan Crow, director of crawl systems at Google, speaking at the Search Engine Marketing New England event in Rhode Island.

Though there was a lot mentioned in Jill's post, including information about PageRank, robots.txt, Webmaster Central tools, Sitemaps, Flash and Ajax, the little-discussed tags already available and a new one soon to be available caught our eye.

Lay off my snippet: Webmasters can prevent Google from showing certain text in the search results by using a simple "nosnippet" tag. Not that you wouldn't want your snippets showing – just that there may be a reason for it out there somewhere.

Caching out: The "noarchive" tag stops Google from showing a cached version of a webpage.

Limited time only: Jill seemed pretty excited about a forthcoming tag from Google called "unavailable_after" which sets a self-destruct timer on page information. This is good for coupons, limited time offers, articles intended to be viewed as previews only.