Verizon's Pixel and Pixel XL Oreo release notes show Instant Apps integration as being part of the software when at the current time this isn't a feature which is actually present in the updated version of Android. The Pixel launcher is supposed to have integration of Instant Apps to make finding and checking out apps a lot easier, and when available will allow users to search for and see Instant Apps right from the app drawer's app search bar at the top and just above the first line of apps, but since Google hasn't made this feature live yet, it's unclear as to why Verizon's release notes mention it as the build that's being sent out to Pixel and Pixel XL owners on the network is the same that Google began rolling out earlier this month.
In addition to the Instant Apps integration, the release notes mention the new Always-on-Display feature that Google will be implementing, while explaining that when you get an incoming notification the view of the display will switch from always-on to ambient so you can actually see the notification content. Before the switch, the display will look like the first image below in the gallery, while after the transition it'll appear like the second image.
Although the current build of Oreo doesn't have these features yet, perhaps the fact that Verizon is mentioning them in the release notes means that they will be added in soon, or perhaps it's just a mistake on Verizon's part. Beyond these two features the release notes go over a ton of other new changes that come as part of Oreo like the notification badges, the notification channels, the autofill feature, and of course the picture-in-picture mode that makes it possible to open an app window on top of an already open app, which isn't too unlike multi-window, although the picture-picture mode keeps the initial app open on the entire screen and simply layers the second app on top of it, while multi-window splits the screen space between both apps. Verizon's release notes don't mention a size for the file download, but since it's moving up an entire version it's going to be large, so downloading the update over Wi-Fi is recommended, as is at least half the battery life or the system likely won't let you initiate the update process in the first place.