One thumbs-down vote for a tool icon replacing the navigation choices in a website. Making the front page visually cleaner by making it interactively more complex is not a good idea. It’s not even good in most browser apps, but here it’s particularly bad, because it clearly reduces utility by making you click twice to get to any of the choices. The options don’t have to take up a lot of space, but hiding them behind a mysterious icon is very strange. Either expose them directly or eliminate them.
Of course this isn’t a big deal, but it’s just a bad design choice. Not everything Google does is good for everyone in every circumstance.