I have read lots of reviews and websites. I am looking for a small lightweight camera with similar functions and image quality of my DSLR. I do a lot of walking and don't want to carry around heavy kit but I do like to photograph landscapes while walking but the camera would need to be capable in other areas too. I like to take multiple exposures for HDR. I am unsure of whether there is really any great difference between APS-C and 4/3.

I am hoping for some ideas as to what camera to go for. My previous kit was a Canon 40d.