Biggest update for me is support for off loading processor intensive tasks to the graphics card. I’ll be interested in how MacPro’s now run Lightroom.
The big updates that are photo related are HDR and panoramic support built into Lightroom. No more round trips to Photoshop or third party plugins.
Facial recognition and tagging is now built in, so their Pro app now has a feature that most amateur editing apps have had to a couple of years now.
The other two things I was very pleased to see was an erase blush for the grad filter so you can selectively remove its effect and a simple thing but something that could get me using Lightroom Mobile more is the ability to add photographs into collections during import.
I have created a little test library and have started using it for testing but for now my real work is being done on V5.
I had a few issues, first it would not run on one of my machines and I have also managed to make it crash when using the crop tool. I may wait for the first point release before updating my Master library and using it for real.
Oh, and the difference between Lightroom CC & Lightroom V6, well if your a creative cloud user then you get Lightroom CC, if you purchase the standalone version you get Lightroom V6, apart from the Lightroom Mobile features being missing the two are at the moment the same, but apart from bug fixes and camera RAW updates, Lightroom V6 may not get feature enhancements like Lightroom CC will.