absolute top class 1

I have now bought the camera since the end of October 2014, the 2,8 / 12-40 mm PRO. In the meantime, my preferred lenses are now complete:

1.8 / 75 mm,
60mm Macro,
9-18 mm wide angle,
2.8 / 40-150 mm PRO without teleconverter

A great camera that does have (available only manual from the Internet) taken due to the many options a little preparation time, but delivers a absolute great quality.
It's just fun to photograph it. And my photo backpack has become a lot easier and saw everything. The image stabilizer and the viewfinder are really excellent. The dials and the trigger everything, so it was in the right place not getting used by Nikon for Olympus.

High ISO settings up to 1600 ISO or long exposures / noise:

From the Olympus OM-D Paper on E-M1 from Franzis I could see an excellent tip. The "noise reduction" parameter (not to be confused with Rauschrezuzierung) should necessarily be on AUTO. He ensures that the appropriate Dark Frame is automatically created. Without Darkframe the noise would increase substantially at a long exposure time. I tried it and am absolutely satisfied with the results at high ISO. However, I have automatically limited to 1600 ISO and found no noise. Possibly you can still well ausreizen to 2200 ISO. (The Dark Frame affects the way on the RAW from). Do not switch off in long exposures of several minutes the camera. This tip is on page 272, if additional information is needed. The book certainly makes sense with this camera. Very informative compared to the manual. Other very good tips on camera and very well explained.

Wi-Fi works well and is with the camera settings (A, P, S, M for speed / aperture / AF / frame / Plus-Minus-Correction / self-timer, inter alia, all very simple to operate from iPhone.
Simply download the App Olympus. The app: OI.Share provided by Olympus free of charge (for Android and Phone). The mobile phone is connected by means of QR code with the camera. Also handy: The GPS data is written to the memory card, if one causes the iPhone. For example, long exposures on a tripod, or when the photographer wants to be in the picture doing itself. Simply ideal in society, for example, quickly erected on a mini tripod.

In summary, I can say now: Super fast AF, very bright viewfinder, versatile adjustment possibilities, which I also use. Especially the flash with slave and remote = RC mode. The compact flash serves as a master controller.

The camera and the lenses are now much lighter than my Nikon. Even the (battery) camera grip, you get free to is a fine thing. The Olympus E-M1 is so great in the hand.
Tiny downside: the handle has to be removed for transporting a bicycle handlebar bag. Batteries degrade but to fast, so it is advisable to take at least a 2nd or 3rd battery with a weekend trip or vacation.
Charging time about 3 hours. The capacity in mA is comparatively much higher at a Nikon D700 and D7100. But as you can to be prepared.

Image quality of the Olympus E-M1: very first with the objectives mentioned in this cream. I miss nothing from my Nikon also excellent.

Switching from Nikon D7100 and many serious and fast lenses I therefore regret in any way.
I am very pleased and can recommend this Olympus camera with the appropriate mentioned lenses without restriction.

However, I have decided to continue using the only Nikon, a D700 with an outstanding specialty lens (shift lens 24 mm). Since there is probably no alternative and the cost would be too high.
However, I have not tried the in-camera distortion correction for architectural shots (Keystone Correction). Thanks Roland for the tip.