Cameras with more dynamic range allow you to take photos with dramatic differences in highlight and shadow areas while retaining detail in both.
Think of a brilliant sunset on a rocky beach: Bright sunset in the background, with dark rocks in the foreground. High dynamic range means more of the extremes will be faithfully reproduced.
Dynamic range test data courtesy of DxO Mark.RX100 V test data on DxO Mark G1X Mark II test data on DxO Mark
Wider, longer, faster lens than predecessor, with good overall optical quality; Faster AF performance; Closer macro shooting; Built-in Wi-Fi and NFC with remote shooting; Decent JPEG burst performance; Excellent build quality.
Localized flare issue when wide open; No real net improvement in image quality over predecessor; Slow burst mode when shooting RAW files; Poor battery life; Video quality is so-so (not like Canon DSLRs).
Pocket-friendly design; Unbelievably fast burst capture; Generous buffer depth, even for raw; Fast and confident autofocus; Very high resolution gives lots of detail in good light; High ISO noise levels much better than most pocket camera rivals; High-quality 4K video with uncompressed HDMI out; Super-fast High Frame Rate video
Very pricey for a compact camera; Still no touch screen; Slow buffer clearing; JPEGs can look over-processed at higher ISOs; Lens doesn't offer much telephoto reach; Battery life is very modest; 4K movies are limited to five minute clips