All advertisers can now benefit from this new AdWords experience.
By doing more in less time, you will first notice that your account pages load 20% faster on average. In this way, you will reach the information you need faster and you will be able to return to your work quickly.
Navigating the page is now much easier as we've removed clutter. In this way, you will be able to take more actions in a shorter time, for example, you will be able to add more than one extension type to your campaigns in a single step.
Note: Google will enforce the new interface on all accounts from January 1st.
Source: www.adwords-en.googleblog.com