Gmail announced on its blog this morning a major design overhaul which will be rolling out to inboxes "gradually."
The new inbox is designed around five tabs: primary (for your human-to-human contacts), social (notices from Google+, which you knew they'd work in somehow, YouTube, and Picasa), promotions (retailers), updates (did your flight get changed? has your package shipped?), and forum (for message boards and group discussions). You'll be able to customize which tabs you see, and train the categories to sort the emails as you would like.
Google's updates to its Gmail design have not always been well received (see: "What Went Wrong With Gmail?"). Users get used to the arrangements and systems they have, and they don't like it when an upgrade requires some adaptations (see: "The Cloud's My-Mom-Cleaned-My-Room Problem"). This is true even if a new product is, by some objective measure, "better" (see: New Coke). Inboxes are particularly sensitive, as they are at the core of so much of our lives, both personal and professional.
In a move that recognizes users' repeated distaste for a switch-up, there is no forced march over to its clean, white shores: Google is leaving users the options of switching back to their preferred style, at least for the time being.