You can pre-order select movies, e-books, and audiobooks and have them appear in your library as soon as they're available. You can also pre-register for select apps and games that aren't out yet.
Starting in August, the Music store on Google Play will start shutting down gradually for users, and you won't be able to buy music. Pre-orders with a delivery date after the shut down won't be fulfilled, and you won't be charged. You'll receive an email for any pre-orders that have been canceled. Your existing music purchases (up to 100K songs) can be transfered to YouTube Music. Learn how to transfer your Google Play music.