"Where it shines, though, is its application and use of photo metadata. Adding categorization to photos is a drag-and-drop action, or a right-click action, or a menu-driven keyboard aware action — on a single photo or multiple photos at once. Recognizing that facial recognition software hasn’t quite migrated to the desktop, Adobe has made it dead simple for the user to add labels to their photographs. Not only that, the design of the UI encourages the use of those labels, making it easy to filter a contact sheet view of photos by one or more labels (categorized by "people," "places" and "events"); or by time, through a sliding timeline or a popup monthly calendar."
Looks like a good replacement for ACD See, which we haven’t found to be very stable.