As with just about any application on the Play Store, updating Google Maps is a continuous process for Google as they are always changing something while doing their best to improve the way that it functions and sometimes this includes adding more features or giving it a more intuitive and user-friendly UI, while other times it simply means making some under the hood changes that improve the overall performance of the app so it just works more smoothly. Sometimes it just means throwing in a fun little easter egg. In a more recent update, Google started adding little bubble indidcators in the Navigation portion of the Maps app so that users could more easily distinguish exits and roads when traveling and using the navigation for directions.
At the time of the udpate it seemed to be that this was more or less a server-side change and couldn't be obtained by simply updating to the newest version of the application, as only a smaller number of users were seeing the feature included. As of today it would appear that Google has started to roll the feature out to more Maps users with more of them reporting that the bubbles have been popping up when using navigation, denoting an exit they're supposed to take, and sitting just above the route but under the street names in the header bar up top.
These new bubble indicators also connect directly to the road or freeway you're currently on and are blue to match the navigation line so there shouldn't be any confusion when glancing at them, and of course they also hold just a small but acceptable amount of information like the freeway and exit number that they're trying to highlight. At the moment there is no way of knowing if this will be Google's final rollout to complete the feature push to all users, but it does seem like it's hitting more devices so there will at least be some new users who will get this experience the next time they open up Maps and use the navigation to get some place. Quite a few users should already be on the latest version of Maps so if you're about to head out to work or anywhere else, try bringing up navigation and see if the bubbles appear.