Again, Yahoo seemed to have quietly updated Site Explorer to include new data. The new data is on the summary page and includes:

Key TermsDelicious ActivitiesTop Delicious TagsSearchMonkey Objects

Here is a screen capture of what I think are the new pieces of the summary report:

Some might think that since Site Explorer is displaying Delicious tags in Site Explorer, that the tags may have some sort of weight in your rankings for those terms.

I find it weird that this is the second update to Site Explorer in the past month or so that Yahoo did not announce. The first was when they added top queries and URLs to the tool.

Forum discussion at Search Engine Roundtable Forums.

Update: Yahoo has now announced it on the Yahoo Search Blog.