A few days ago AdSense - in the new interface - began rolling out 'Ad Styles' and have just made an official mention:
Introducing ad styles: an enhanced feature replacing color palettes
So far, I have to say that I like it.
Ad styles extend and enhance all of the functionality of our old color palettes. With ad styles, you can create customized combinations of colors, fonts, and corner styles and then easily apply these to the ad units and search engines across your site.
Yes, I am admitting to liking a Google feature/service/update... ...and the world as I know it has not ended.