Its been over a week now that the homepage of my 1.5 yr old site has stopped showing fresh tags in Google. So, when you search for "example" in Google, instead of www.example.com/ - 15 Sep 2006, it shows www.example.com/ only.
Interestingly the cache is updated regularly. When I searched the logs for past 7 days, it showed that Googlebot was visiting the index page everyday.
Unique content is added daily and thus index page gets updated as well. Also the site has a pretty high number of quality backlinks. But why the fresh tags aren't showing no more is a mystery to me.
I'm a little concerned now since yesterday the main page vanished from Google for one of my primary keywords. It is back in Google today but still does not show a fresh tag.