We've been using the UI for a few days and here's what we think:
The new look is designed to be consistent with the new look of all the Google properties. The intention is to modernize and clean up the old UI.
It looks...OK to us. Perhaps the new UI is designed with mobile users in mind, but it all seems a little big. The grey bar up top takes up a lot of screen space and there seems no real point to that.
To be honest, our first reaction was that the new UI is a bit clunky. The huge navigation menu just pops out when you hover over the Google logo and it just felt easier to navigate through the old UI.
Where's my trends?
There's been no official word on this but the new UI has apparently removed Trends from the Google Plus search page. A bug or intended feature? We've reached out to Google for an answer and we'll let you know if we hear anything.
One step forward and two steps back. The concept of modernizing and connecting the different Google services is a good one, but it feels rushed and poorly executed to us.