The update is based on Android Nougat 7.0 and doesn’t bring any change in the Nougat version. It has started rolling out as an OTA update and should reach your device in the coming days.
If, however, for some reason you don’t receive the update notification, you can check for the update manually from Settings – About – Software updates.
Also, the new update arrives with build number VS98812B and VS98729A for LG G6 and LG G5 respectively. Further, your device should be on the build number VS98811A and VS98728B for LG G6 and LG G5 respectively to receive this update.
Like any other security patch, the update takes care of various security vulnerabilities and brings along fixes to existing bugs. You can also expect performance and stability improvements from the update.