Now, many are not happy about it - as is always the case when Google makes a change.
Google has decided to open up a single thread to provide feedback at Google Web Search Help. Jessica from Google is the brave Googler who created the thread, asking for feedback. She wrote:
As many of you have noticed, we've rolled out some changes to the way Google.com looks to users in the US. Specifically, we’re making some design improvements to our search results page, moving the tools from the left side of the page to the top. For Image Search, know that the Larger Than and Exactly tools are temporarily on vacation. We'll update this thread when they're back in town.
If you have feedback or questions about these design improvements, please post them to this thread.
To give a little background about why we've made the change: the new overall design follows our updated mobile design. From our tests, it seems to work well on desktop, and we’ve created a design that works well on a wide variety of modes and devices. We’ll keep updating and improving our designs as always.
So point number one, the image size filter is coming back soon.
Point number two, this top navigation is here to stay, at least for the near future. Google is constantly tweaking things. So the design may change slightly based on your feedback. But Google tested this and it fits more closely with the mobile design and thus they want to keep it.
So if you are not happy with the design, make sure Google knows why at the Google Web Search Help thread.
Forum discussion at Google Web Search Help.