Woah. Google SearchWiki

Google says:

Today we’re launching SearchWiki, a way for you to customize search by
re-ranking, deleting, adding, and commenting on search results. With
just a single click you can move the results you like to the top or add
a new site. You can also write notes attached to a particular site and
remove results that you don’t feel belong. These modifications will be
shown to you every time you do the same search in the future.
SearchWiki is available to signed-in Google users. We store your
changes in your Google Account. If you are wondering if you are signed
in, you can always check by noting if your username appears in the
upper right-hand side of the page.

The changes you make only affect your own
searches. But SearchWiki also is a great way to share your insights
with other searchers. You can see how the community has collectively
edited the search results by clicking on the “See all notes for this
SearchWiki” link.

This could be pretty big.  Or a pretty big headache, once people start spamming it.  It will be interesting to see how this rolls.