From Google Apps update alerts:
Over the next few days, we’ll be rolling out a feature that lets you view Gmail attachments and save files directly to Google Drive without ever leaving Gmail. The next time you open an email with attachments, you’ll see new previews of the files at the bottom of the email. When you click on one of those previews, a full-screen view of the image or document will appear. You can now also save your attachments directly to Drive simply by clicking the Drive button that appears when you hover over the preview.
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