I didn't know there was a new client until I saw your question today and it appears that indeed, there is a new interface. Yes, it is a new feature of the program. If you look closely, from start you can see that the client acts more like a desktop-companion rather than a common application.
I do like how the Search function was implemented, making it easier to search for installed applications, articles and recommendations.
Although I liked the old interface as well, this new one actually speeds things up and the icons used provide a fast way to access sections.
Another nice feature is the ability to hide various sections leaving only what matters. For example, as you see in the image below, you can click on those icons to hide the sections. Many users prefer having only apps, then you can select only apps, others want to stay in touch with latest technology and check to see articles only.
If you ask me, this isn't a drawback. The client was "re-imagined" to make things simpler and easier.