Google is in tight competition with bing (Microsoft) in terms technology and market positioning of its products, recently Google has updated its User Interface which is much similar to bing.com search results pages. Even though this option is available with earlier Google search results page under web options but they make it available now.
I feel Google is just imitated the Bing search results page but somehow i like the way bing results are presented may be due to color combinations or font sizes, it has more web 2.0 look now, who knows Google might make more changes to its interface in near term.