Google is notoriously slow and calculating about changing it the user interface of its services.
In fact, Google hasn't made any major changes to the look and feel of Google Maps since its launch in 2005.
On Friday, the company launched several refinements to Maps--the biggest changes to its look since launch. While you might not notice these changes immediately--unless you are a hardcore Google Maps user--they are designed to enhance the readability of the maps.
As seen above, the thick street outlines that can make maps harder to read have been eliminated.
Google describes the update here:
(L)ocal and arterial roads have been narrowed at medium zooms to improve legibility, and the overall colors have been optimized to be easier on the eye and conflict less with other things (such as traffic, transit lines and search results) that we overlay onto the map. Hybrid roads have gained a crisp outline to make them easier to follow, and the overall look is now closer to an augmented satellite view instead of a simple overlay.