Google looks to have begun an update to the Google app for Android devices today, and while not everyone is guaranteed to receive the update before the day is over it shouldn't take more than a few days (if that long) before users notice the change. There is at least one notable addition included in this new version to the Google app which is the Nicknames feature which some have been using since 2014. Nicknames is a feature that Google began deploying to the app for some users last year, which allows you to tack on a nickname to people in your contact list.
How this becomes beneficial really begins to emerge if you have multiple people in your contact list with the same name. For example, if you have three Ryan's in your contact list, but one is a close personal friend, one is a brother and the others is a second uncle, you can attach nicknames to all three of these people, thus making it easier to contact them using the voice activities of the Google app by saying something like "send a message to my brother." If you've already gotten the update to the Google app or are downloading the apk file which you can find here, you can find the Nicknames tag inside of the Accounts and Privacy section of the Google app settings, however adding Nicknames is done from your contact book when editing an existing contact or adding a new contact.
This appears to be the only change that users can interact with at this time, however, Android Police points out that there are a couple of features that could likely be in the works for either this version of the app update or another version coming in the future called Trusted Voice and Seamless Hotword. Trusted Voice is basically just like it sounds, a new smart lock feature coming to the Google app for compatible devices although it shouldn't be considered a suitable replacement for a more secure option like Trusted Devices or a PIN or password. Seamless Hotword looks to be something that Google is testing out internally and unfortunately there aren't any details on what exactly the feature would do or what it is.