We've watched as the Material Design guidelines have evolved over the years. When they were first introduced, Google went through a number of their apps and web services to give them a redesign that matched the new design style. Then, Material Theme came out as the next evolution of Material Design and this too was accompanied by multiple redesigns to both applications as well as web services. We've seen the redesign hit web services such as Gmail and Google Docs, and now it has made its way to Google Maps on the web.
The new design style has been in the works for well over a year. It took Google a while before they felt it was ready for prime time, but then we started seeing a number of apps and websites being redesigned. We noticed small changes to the Google Maps application until the full overhaul began rolling out with version 9.80.2. This change only affected the mobile application though as the web version of Google Maps has been left untouched since its first Material Design redesign.
Thanks to a report from Android Police, we were made aware that the new redesign was pushed to the web version of Google's mapping service. Things are now looking a lot more like the mobile application with the search box receiving rounded corners, a cleaner UI (with more options), and fewer shadows. The rollout doesn't seem to be ready for everyone though as I still see the previous Material Design style on my desktop (at maps.google.com) and on my Pixel 2 XL.
So it seems as if Google is gradually rolling out this new look to Google Maps. Those who use the service on the web may want to keep an eye out for it as there are a number of UI and UX elements that have changed with the new design.