We first got an inkling of such a feature when someone spotted it on search cards for local businesses. Located between the attraction's address and photos, it's not unlike Amazon's Q&A section located above the reviews. It's also a way for Google to take advantage of expert Local Guides. Rather than poring through user opinions, you can ask a specific question to find the information you need. At this point, of course, there aren't a lot of responses or participants yet.
Another interesting addition is picture-in-picture, something that came up in teardowns last month. As Android Police notes, if you're running Android 8.0 ("O"), you can run Maps as a small floating window on your home screen. The feature is most helpful during navigation, where it can show your ETA and distance without the need to go into the app. Right now, however, the feature is very buggy, with text elements and the map all jumbled together.
Two other possible upcoming features are monthly driving stats, which is much like Google Fit for your car, letting you know your trips, average driving speed, time in traffic and (of course) time saved with Google Maps. Finally, Google is previewing new navigation notifications, telling you whether it's running in the background or foreground -- handy if you're arriving at a complex intersection, for instance.
As always, don't count on these features as this is just a beta for now. Nevertheless, the Q&A part at least is likely to become a part of Maps, and possibly soon. If so, you can probably expect to see it within a few months, but if you can't wait that long, download it at APK Mirror (don't worry, it's safe and signed by Google ) or Play. Remember, you'll have to agree to be a beta tester first, and it'll overwrite your existing app.