Hi, John - Having made the switch to digital late in the E20 life-cycle, and being an E-1, E330 and E500 shooter, I'm reasonably well positioned to answer your questions. (But let me add that I am part of the Olympus Visionary group, and am given and loaned equipment.)
First, someone else here made the comment earlier that they are still using film and having tried a digital point and shoot don't want to switch to digital; that's a bit like saying 'I've used a Kmart disposable camera and it sucked, so why would I want one of those high-priced Leica things?' Film is dead. Period. End of story. It is as dead as glass plates were when film came along. It is an artifact of the previous era in photography. Will there be film around for some time to come? Sure. Will there be people who stick with it as long as it's around? Sure. Will it be a fine art medium long into the future? Most definitely. But photography as we know it is now digital - and thank God it is. I shot film for more than 40 years, and I can do things with digital that I never dreamed of doing with film, and do them with real confidence. Do I miss my Leica Ms and Oms? Yes - but what I miss is the form and function of the boxes - and the incredible image quality of some of the final generation of Leica lenses, not the film I put in the camera.
Okay - So 4/3. I think Olympus made a real mistake going with 4/3 because they boxed themselves into a smaller corner than Nikon and Canon with their larger sensors. It's not a question of pixel count - I have just finished a corporate job calling for a display of images printed up to 30x40" and I shot it with the E-1 - 5mgp, and the E330 - 7.5 mgp, and the company doing the printing commented on the smooth tone gradations, color quality, and said there was not problem producing the size and quality we need.
So the problem isn't pixel count - it's low-light noise. Getting low noise levels out of the smaller sensors is tough. There's no question the new MOS sensor in the E330 does a much better job of handling noise than the sensor in the E-1 and E500, so I have real confidence that we will see even more improvement in the next iteration of the E-1. But people who want the peaches and cream look produced by the Canons - a look I don't like - will not be happy with the 4/3 images. (Of course those people have apparently already forgotten what film produced images look like - blow up a Tri-X frame to 30x40 and it looks like it was produced using light sensitized rocks. (Oh, did I neglect to say that most of what I shoot I shoot at 800 iso?
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If you can get an E-1 at a low price - and you can - grab it; it is one of the true steals on the market today. The body is built as well as the best of the Nikon and Canon pro bodies, if not better. It could not be more solid, dust and water resistant. It takes the proverbial lickin' and keeps on tickin.' And when I say 'tickin' I mean it - it is quiet. How quiet is it? It is as quiet, if not quieter, than a Leica M6 - the quiet standard in 35 mm. It is an ergonomic gem, fits the hand perfectly, balances perfectly, and handles like a Miata - so what more do you want.
The lenses - and I'm talking about the 'pro' line - are terrific. The 11-22 zoom is a real steal, and the 35-70 f 2 is a killer, if heavy. My only complaint about the lenses is that they do suffer from veiling flare when subjects are heavily backlit. That's not something I'm used to coming from Leica M aspheric lenses. However, and this really is an important point, Canon and Nikon lenses suffer from the same problem, so this is more likely a factor of zoom design and optics than anything else. And you just figure out how to shoot around it or make use of it.
The bottom line is that I love the E-1 and E330 with it's live LCD display. I do street photography, corporate and editorial work, weddings, and documentary photography of families - and the Olympus equipment is suited to all of those forms. Take a look at the work on my website, almost all of which was shot with the Olympus digital equipment:
www.bdcolenphoto.com
So forget Nikon, forget Canon - and grab an E-1 while you can.
Best B. D.