Vanessa Fox posted an update at the Google Webmaster Central Blog on what the date and time displayed on the Google Cache page really means. The date displayed technically shows the last time Google "retrieved" data off the page, meaning if you have a page that hasn't been updated, and Google visits the page and sees that it was not updated, then Google will not retrieve any new information from that page and it won't update the date displayed on the cache page. Here is an example of the cache page of Search Engine Watch, carefully look at the date in the Google cache, right now it reads, " is G o o g l e's cache of http://searchenginewatch.com/ as retrieved on Sep 1, 2006 08:07:09 GMT." And then compare it to the last article that was posted, they should be within a few days of each other - since this site is crawled frequently by Google.
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