Yesterday, after Google uploaded and pulled it out here is the Finding Fresh Results blog () once again.
"What makes providing the latest information harder is the small amount of time we have between the page creation and when we'd like to serve those results to you.
Despite these challenges, one thing should not be hard: finding the freshest results on the page. To make it easier for you to spot the newer pages among the search results, we are now going to tell you how long ago we've seen a page containing what we think you're looking for.
For example, if on August 6th you were searching on Google.com for latest financial information following the Friday financial sector action, here's how that result would have looked in the past:
From this you could only see that we crawled this page at a day level granularity. But now when you do this search you will also be able to tell how long ago we noticed this page, so you can quickly pinpoint which of these is results is likely to contain more recent information. Here's the same example showing the annotation that tells you there's something new in the results we've seen recently.
For more, go to sitemaps.