I just saw this over on Search Engine Roundtable. It appears Google is messing around with a new user interface. It basically looks the same with a few more items thrown in. First thing I noticed was the tabs at the top. Search Engine Roundtable has links to a few forums discussing the new UI. The SEO UK blog has a screenshot of the UI. SunnyMonkey (at SEO UK), has made a few notes on his screenshot to help you see the changes.
It’s nothing great but there’s a lot more color. I dunno if I like the color combo they chose. Too many different colored pastels. I dunno if I like the tabs. I think I like it how they have it more right now, just the plain text links. Oh well, they’re google and can do whatever the hell they want.