Yahoo Search is currently undergoing a new index and ranking update. I first reported it at Search Engine Roundtable and then the Yahoo Search Blog posted on it saying it should be done this morning.
On the Google front, there is still chatter in the forums about a possible Google update. Google’s Matt Cutts debunked the update, calling it “normal flux,” but some people are skeptical.
Finally, I wrote a piece at my personal blog called Should Search Engines Update Search Results During Holiday Season? about the issue of whether updates shouldn’t happen during holidays.