Although it keeps the same flash as the E-P3, the E-P5 gains a more traditional front dial. In addition, Olympus prides itself on the dearth of screws on the body -- just a handful on the bottom plate -- but it means that the screw-on grip of the E-P3 has changed to a shallow fixed grip on the E-P5.
Rather than a fixed OLED display, the E-P5's uses a tilting capacitive touch screen, similar to but higher-resolution than that of the E-M5. Olympus tweaked the design with side grips for easier pullout.
In another more traditional move for the E-P5, Olympus replaced the vertical dial with a thumb grip and added a standard thumb dial on top. The new 2x2 Dial Control allows you to quickly program the dials to toggle between pairs of functions.