It would be hard for the top of the E-M1 to feature more controls, or look more OM-esque - the On/Off switch on the left shoulder and the new button turret next to it are reminiscent of the original OMs' film winding handles and Auto/Manual switches. From here you get direct access to focus, metering and drive modes, along with one of the E-M1's new features - in-camera generation of high dynamic range composite images. The camera has a unique trick here - it automatically previews how the HDR image should turn out in the EVF, by pulling up the shadows and re-balancing the local contrast.
The positioning of the power switch divides opinion in the DPReview offices - some of us think it's just fine, others dislike it. Most cameras these days place this control close to the shutter button, allowing quick operation by your index finger without having to change your grip. The E-M1, in contrast, requires you to shift either your left hand from under the lens or your right hand off the grip, which could cause you to miss a shot. It's a relatively minor point, but one worth pointing out.
On the right-hand side, the camera's mode dial has gained a sprung, toggle lock. It's a nice implementation; if you like your mode dial locked, you simply lock it after making a change, but if you don't, you can leave it unlocked. Beyond this, the right shoulder is dominated by the two control dials, with the Fn2 and REC buttons nestling between them and Fn1 sitting on the angled shoulder of the camera.