I've been away from photography (and this forum) for awhile, but have recently gotten the flame re-kindled. I need to catch up on the latest and greatest and thought that I'd ask a few questions here. I currently shoot with an Olympus E-M5 and a Nikon D300. Nikon recently announced a new DX body (D500) which got my G.A.S. going again. But I'm really not sure whether I want to continue down the Nikon road, since I use my E-M5 much more often. So, here are my questions: 1. One thing that I'm interested in shooting is wildlife and birds. (The D300 which works quite well for this.) One of the weak points of m43 has been continuous focus/subject tracking. Has that improved in the newer models, and if so, which bodies are best at this? 2. Another thing I shoot a lot are landscapes. With my E-M5, I've programmed a function button to shoot a burst of 5 frames separated by +/-1ev in order to merge later to HDR via software. (I do this A LOT.) I see that the E-M5 MarkII has a dedicated HDR button. Exactly what does that button do and how effective is it realistically? Can anyone share a comparison of images using and not using the HDR function? Thanks!