Hi, I got the opportunity to play with the Panasonic GH4 at the Dublin photo fest (also gave the Panasonic representative a bit of a ribbing for mentioning that they had a 35-100 F2.8 coming in a smaller form factor ). He was a great sport and a lovely guy. But I got to have a play with the GH4 and walked away super impressed. Those of you with orders down will be very impressed and happy. Panasonic had the two GH4's on hand to play with. The first was hooked up to a 4k display with a Nocticron attached and was shooting images of attendees. The video quality was unbelievably good. They also had a second one on hand (unfortunately no 15mm lens to play with) with the 12-35 F2.8 attached. I had a go of this and was particularly interested in having a go of the focus tracking to see how that performs. In the very limited tests that I did, it worked great. However that being said, it wasn't exactly the most taxing On the model that they had there (with pre production firmware I believe) the tracking locked on very quickly. You touch the subject that you want tracked and the yellow 'target' box tracks it across the frame. It appeared to be very effective. Granted it wasn't exactly the most taxing scenario that I tried - tracking people moving in the crowd and a few kids running around the place. So real world opinions would need to wait. The DFD appeared extremely quick but perhaps subjectively not quite as quick as the EM1 with an equivalent 12-40 lens attached. We are talking splitting hairs here but it was something that I noticed. However my real take away was that this is a fantastic stills camera. Image quality is beautiful. AWB was pretty good. AF is blazing quick. The UI was again, subjectively speaking, much nicer than my EM1's UI and very simple to operate. In fact of all the cameras at the show, I really feel that Panasonic and Olympus had the most innovative products on show.