• In the Folder panel, you can now move and/or delete multiple folders at one time.
• In the Collection panel, Option -drag (Mac) | Alt -drag (Win) a collection to duplicate it. More specifically, if the collection is loose (it’s not in a Collection Set), Option -drag (Mac) | Alt -drag (Win) until a thicker line appear between two items (indicating that the collection will be duplicated), and release. To duplicate a collection within a Collection Set or to duplicate the collection into a different Collection Set, Option -drag (Mac) | Alt -drag (Win) the collection on top of the Collection Set icon (watch for the highlight) and release.
• Stacking is now available in Collections.
• At the top of the Filmstrip bar, the selected image’s folder or collection is displayed. (This is really handy when in other modules.)
• The Flag attribute is now global.
• You can filter and/or search images based on their Metadata status. Images will be assigned one of several different statuses including Changed on Disk, Conflict Detected, Has Been Changed, Unknown and/or Up to Date).
• You can also search/filter on Map Locations and GPS Data (GPS Location or No GPS Location).
• That folder structure that you carefully crafted in the Develop module to hold your presets is now maintained both in the Import dialog box as well as the Quick Develop panel.

In LR4 is it now possible to filter based on Exposure Bias? This would be a big help in HDR
Great suggestion – Would you post it here so that engineers and other customers can comment? Thanks!
http://forums.adobe.com/community/labs/lightroom4/
Julieanne, has the performance of moving folders been sped up? Right now on LR 3.6 (and before) it’s painfully slow, to the point where I have taken to doing it outside of LR and then pointing LR to the new location.
What I’m doing is moving a folder from my main catalog on my PC drive to an external backup drive (to which I’ve already backed up the folder). So I delete the folder on my PC through the OS, and then point LR to the same folder on the external drive. Much faster…although I know I’m *supposed* to do all changes in LR so the DB can maintain itself.
Chris