We wanted to go beyond simple color customization, so out of the 30 odd themes we’re launching today, there’s a shiny theme with chrome styling, another one that turns your inbox into a retro notepad, nature themes that change scenery over time, weather driven themes that can rain on your mailbox, and fun characters to keep you in good company. There’s even an old school ascii theme (Terminal).
It’s added to a Themes tab in your settings. Note some themes are dynamic and may change throughout different times of the day. “We’ve also done a minor facelift to Gmail’s default look,” Google adds.
Personally, I prefer these three: 1. Pebbles; 2. Tree; 3. Mountain. Yeah, looks like I’m a sucker for minimalism and nature.