The photographer I work with sent me that link. This was my reply:
I saw that link on some site, but didn't follow it, because those pieces tend to be in the "little engine that could" category. Since you sent it, I did follow it and...OMG... IT'S THE LITTLE ENGINE THAT COULD! Well, it could and does for what he does. Maybe it's the way he prepped the files for the web, or the files were small, but the technical quality was feh. When I was shooting HS reunions for Leonard I brought Ben [my son] with me, because the Chief was out of town. He was 10 and brought his Canon A70 P&S camera. I printed out a couple of 5x7's of his pictures, and one of them sold. I guess that A70 was a professional camera too. I love µ4/3 and like what I get, so long as I play to its strengths.
There's no end to the conversations in the various forums, which I'm sure we've all read, comparing one format to another, or even the new model to it's predecessor. You should read all of the wailing and gnashing of teeth in the Fuji forum at that other site about the X20. I agree completely with you Bruce, that it's important to stay within the capabilities of the equipment and obviously there are some things you wouldn't be very successful at using u4/3s. I think we've also all seen examples of photography using "lesser" (than FF, or medium format, or large format... ) equipment that puts to shame the results some "professional" photographers get using that D4 and the 70-200.
I'm not blind - I've gone back and looked at some of the shots I've taken using the D700 and the 70-200 and yes there is something there, it's not intangible. I would say that there's definitely a diminishing return though. If the conditions are not so severe that it requires the capabilities of the very best DSLRs the quality that the current crop of u4/3 equipment can produce can most certainly be considered professional quality. If your printing 8x10 or 11x14 prints I'm pretty sure you'd be really hard pressed to pick out what camera shot the photo. I don't print a lot and the largest I've ever printed is 20"x30" shot with the D700 (grandkids group shot) and I had to up-sample to get the DPI I wanted. I hope to do the shot again soon with the EM5 and I expect the results to be as good - heresy to some I suppose, or maybe I'm just delusional - but I don't think so.
There's also the perception of the target audience to consider. We as photographers, whatever level we may be at, are likely to be far more critical and knowledgeable than most of the viewing public. This is the iPhone (oh how I hate to use that word) generation. There's a lot of people who think their blurry camera phone pics of the kids are great... pretty sure they don't see or appreciate the difference between the formats. I don't know if the various formats (sensor size) will, over time, improve the same amount but it's surely going to keep improving and who knows, in the not to very distant future the next generation of u4/3 may be equal to today's generation of full frame cameras (speaking of quality). I don't believe that is really a stretch. It seems likely that the very best equipment will plateau at a level where any further improvement will be impossible for us to see, kind of like having a speaker that could faithfully reproduce frequencies up to 50kHz, can't hear it.
Camera and lenses are tools. We simply select what fits our style and what makes the job for us.
Except for action, mirrorless cameras are doing a great job and they are selling very well.
Their small size and low weight are conveniences. I see more and more professionals embracing these cameras and they are doing well.
I have not updated my EPL-1 because I cannot find reasons to update, especially when I am not an avid low light shooter. I find myself using the little camera often and reaching for it when I need a walkaround camera.
I have said in the past that eventually all or most cameras will be mirrorless. I think Olympus has already proven that a dSLR can be made smaller, lighter and competent without the mirror.