It's Pinterest's most-requested feature of all time (with early beta tests showing more than three million pins have been saved to nearly 100,000 separate sections) and while it's hardly groundbreaking, it is common sense. Why did it take so long to arrive? Especially when you consider the likes of Instagram and Google have been "borrowing" heavily from its user experience offering. If you've been waiting for more detailed organization, the feature is rolling out now across all platforms and will be available to all Pinners in the coming days.