In my opinion, the bigger unanswered question is how far will this redesign go?
The name of the game for Google these days is unification. The company has unified its privacy policies. It created a unified "black bar" across Google properties. It's even pushing developers to unify the Android design. Heck, one of the reasons behind Google+ is to unify Google services by infusing them with a social layer.
But the new interface doesn't look anything like the rest of Google. What gives?
One possibility is that instead of making G+ look like other services, other services will soon look more like G+. Let's think about this.
A few years back, despite some opposition, Google expanded its search page beyond the ten blue links by introducing the "Everything" navigation sidebar. With the recent YouTube redesign, left-hand navigation was added to Google's second biggest property as well. Other services like Gmail and Google Docs have had left-hand navigation from the start. And from the day G+ launched, it had limilar left-hand navigation.
These navigation bars have always consisted of text links, sometimes with small icons. The new Google+ redesign flies in the face of this trend by emphasizing the icons and downsizing the text. I will not be surprised if one day the text disappears entirely.
There is only one precedent for this kind of change. The recent Gmail redesign. Now, the left navbar is still text-based. But the rest of the navigation elements have scaled down on text in favor of buttons. Is this a whole new trend in what we can expect from Google? How would this look elsewhere?
Google+ is a powerful social network. But it's still fairly simple. It's got a few key areas that can easily be represented by a handful of icons, like Home, Hangouts, Circles, Profile, and Photos. Google search has more than a dozen other search engines baked in, including Recopies, Flights, Applications, Patents, Blogs, Books, Images, Videos, etc. Many of these sub-searches have their own filters that also live in the left-hand bar, like cooing time, location, size of photo, date range, etc.
The G+ icon-based design saves horizontal space but it takes up a lot more vertical space. Only a few icons can fit in that column, especially on smaller screens. Can Google fit all their search options into a few icons?
Possibly. After all, the G+ navbar is flexible. Icons can come and go as they're needed. Kind of lie what Google already does with search options. They also have hover-over elements. A single icon, if you hover over it, can reveal many search filters.
If Google chooses a similar navbar for search, it will save horizontal real estate, which will leave more room for the things you care abotu: search results.