Both Yahoo and Google seem to be testing new search results pages.
Karl Ribas found that Yahoo is testing a design that has a thin top blue bar above search results. The blue really doesn’t remind me of Yahoo—Yahoo to me is about the purple and white colors. But the blue does remind me of Microsoft.
Philipp Lenssen reports that Google is once again testing a new user interface for search results. You can see from the screen shot Philipp posted that Google has placed vertical search options as well as related searches on the left side pane of the page. You can reproduce this yourself, by visiting www.google.com/ncr and entering in a snippet of code in the browser URL bar.
Postscript on June 15th: I reported today seeing Yahoo not only test blue but also purple, as a color for the header. Here is an image: