We've just released a significant redesign of our public transit map tiles!
I wrote a blog post about it on the Google Lat Long blog:
"Before, the transit map was placed on top of the base road map, obscuring some important information in the base map and competing visually with the complexity of the road network. With this redesign, we're changing the entire base map to put more focus on the transit lines, and lower the prominence of roads. We hope you'll agree that the result is a cleaner, less cluttered map that will make it easier for transit riders to get around."
Here's a nice quote from 41latitude.com:
"Make no mistake, these simplified maps are gorgeous. They’re immensely readable, and the lack of bright colors gives the maps a professional aesthetic..."