We got our first taste of OxygenOS 11's new interface via Android 11 Developer Preview 3 for the OnePlus 8 lineup earlier this month. Despite OnePlus's claim that DP3 would be the final developer preview, Android 11 DP4 has just been pushed for the OnePlus 8 and 8 Pro, adding a number of minor tweaks.
Image credit: brmbjn on OnePlus Forums
You can view the full changelog above, but it's almost completely bug fixes with the exception of a few minor gaming-related improvements. There's a new "gaming tools box" to quickly switch between a few gaming-related apps, as well as something to prevent accidental touches while you're in the zone.
The update weighs in at around 2.7 to 2.8GB and comes with the September security patch. Since OnePlus's official forum post isn't up, there aren't any official download links available just yet, though you can use the Oxygen Updater app to expedite things.
The official OnePlus Forums post for the update is now up, and it includes all the download links you'll need for various versions of the OnePlus 8 and 8 Pro.