Google is testing new features in Gmail that would radically redesign your inbox, according to leaked screenshots obtained by Geek.com.
It's worth noting that Google is always testing new stuff for its products, and just because screenshots like these leak out, doesn't mean the changes are coming any time soon, or even at all. Google typically changes Gmail slowly, so it's unlikely this change will come right all at once.
Still, it gives us an idea of how Google is thinking about Gmail. In this case, it looks like Google is experimenting with ways to clean up the menu on the left that organizes your inbox, chats, and labels.
Here's what the experimental inbox looks like. Click the image for a larger view: