There's no ETA for when/if these features will go live, but here's what you might see in the near future.
We've seen the Google Play Store go through a lot of changes over the years, including ones both big and small. Version 8.4 of the Play Store is rolling out to users now, and while there's not a lot to see on the surface, there are quite a few features hidden under the hood that give us a glimpse of some exciting things that we could see in the near future.
The folks at Android Police recently conducted a full teardown of the v8.4 update for the Play Store, and the biggest thing discovered was the mention of audiobooks. It's assumed that Google will sell audiobooks alongside their text counterparts within Play Books, but the way through which these will be distributed is currently unknown. We might be able to play them through Play Music, Play Books, or an entirely different app we haven't seen yet.
Paid and free audiobooks will be available, but you'll have to pay for most of them.
Most audiobooks will have a price tag associated with them, but just like titles already available with Play Books, you'll be able to get your hands on a few free options as well.
Also new are notifications within the Play Store. You'll be able to access your notifications from the left-hand menu in the app, and the notifications you get will likely have to do with new app releases, sales, updates, etc. The notifications will work for both apps and games, but don't worry – none of these will actually get pushed as full system notifications.
Lastly, the teardown for v8.4 also revealed the ability to automatically update only system apps and not third-party ones, the removal of the option to pause apps for download until you're connected to Wi-Fi, and a new "deal of the day" section that'll more than likely showcase daily deals on apps, games, movies, etc. throughout the store.
Again, while none of the above features will be available for you to access right away in the v8.4 update, you can grab the latest APK here.