I have used Olympus PEN-system since summer of 2009. With E-P3 and new Olympus 12 and 45mm lenses it has grown into a matured level for me. Image on the left has everything I need for over 90% of my images.
I have travelled a road from 35mm film system cameras to medium and large format cameras, from there to best digital backs and 35mm size digital system cameras. As smaller cameras I have tried all kinds of point and shoot cameras (both film and digital) and APS-C size digital system cameras. This does not mean constantly leaping from camera or system to another but owning tools according to needs.
Every camera is a compromise. You get something and lose something. During my professional career sheer quality with the best workflow was the prime qoal. Issues like portability, weight or size were not very important for most of time.
Now I do photography to express other things and need a tool to suit my way of doing it. I want to be able to print with no compromises in quality in A3 and A2 sizes and high quality up to A1 or A0. But I want also portability. I always want to use a viewfinder, keep looking through it without any need to chimp or because of camera. I need a camera that can be controlled without looking at buttons.
I was very interested in Olympus PEN -system since the beginning in 2009, used it and learned to get every drop of quality out of it. E-P1 and E-P2 felt like my system even though lack of prime lenses and restricted software support (LR2 conversion was horrible) plus slow autofocus have been frustrating at times. But now the pieces have fallen into their places. Olympus E-P3 with high quality, fast prime lenses fills my needs, finally. Now, after a month´s usage I have really grown together with E-P3 and it is now configured just the way I want. E-P3 is the ultimate ETTR (expose to the right) machine. With it and in body stabilisation I can shoot perfectly exposed, sharp RAW images in most available light conditions. Lightroom 3.5 seems to do a very good RAW conversion from E-P3 files.
I have other lenses and equipment for this system of course, actually a lot - and I have full frame 35mm and medium format digital back systems alsoas well as P&S. But the big ones are for specific planned needs. For those 10% of situations.
Of course I am not claiming that my new rig is perfect and final. It never has been. I am happy to get all the improvements that future will bring. But I could just as well keep shooting with this body, viewfinder and those three lenses if this was the final level of optics and engineering.
A full frame 35mm DSLR is an overkill in size and weight unless there is a specific use where it gives noticeably better final in-use image quality or other benefits compared to E-P3. These uses seem to arise less and less. My two D3xes live mostly a very relaxed life. In contrast my 5D2s with lots of lenses do mostly music videos - by my son.
I have always used black cameras since metal OM-1s. For a change I wanted to go back to that style. They only call these silver now...