Google first showcased an AR navigation view for Maps at Google I/O 2018. No timescale was given at that point, but thanks to a report by the Wall Street Journal, we know that it's going to be landing on your phone soon.

The WSJ got access to a phone from Google with Google Maps AR on it for testing, putting into place a lot of what we already know about the system.

https://video-api.wsj.com/api-video/player/v3/iframe.html?guid=EC191DA8-E7C1-4E03-8585-8B6E6EEA115D&shareDomain=null 

The new AR navigation will add real world imagery to your mapping view, so you can hold up your phone and you'll see the direction you need to walk and where you need to turn. It uses huge arrows so it's completely clear, a little like driving in Mario Kart, while identifying what you're looking at around you.

Google reports that it can use visual recognition to help locate you, in addition to the normal network and GPS location finding. The key point here is that, using AR, it will better know which way you are looking, without having to rely on the often hit and miss compass. 

It's not a system that you're designed to use all the time when walking, but more of a glance and go assistant. Walking in a place you don't know with your phone in your hand is a sure fire way to get yourself mugged - or worse - drain your phone battery really quickly. 

Engadget reports that Google Maps AR navigation is going to be rolling out to Local Guides first - i.e., those people who like to write reviews and submit them to Google Maps - and that the system still needs some testing before it will hit universal availability. 

Again there's no real timeline to indicate how or when this will arrive, or if it will be geographically restricted.