Adobe released August update for Lightroom and Camera Raw (ACR). These updates are focusing on improving performance and workflow.
GPU acceleration
Lightroom and Camera Raw can now take advantage of more powerful graphics cards to improve performance, also with high resolution monitors (4K and above).
PNG Export
Lightroom and Camera Raw can now export images in PNG format
You can import PNG files (you could do it for quite some time) and now you can also export images as PNG (popular uncompressed format for the web).
Collections Colour Labels
You can now add colour labels to your Collections and Collection Sets:
Batch Merge HDR and Panoramas
Lightroom now allows you to batch merge your panoramas and HDR images by letting you create stacks of images for HDR and panoramas (seperately) and then creating panoramas or HDR compositions from stacks (right-click on the stack and choose Photo Merge > HDR (or Panorama or HDR Panorama).
You can find more information about the new features on Adobe website.