Upload & Sell: On
It is very interesting to read everyone's impression of this camera. My own view is that this camera makes a very serious run at a pretty big piece of the pro market and will be enticing to quite a few amateurs as well. For the wedding/portrait and many photo journalists this will be a quite compelling camera. I think the killer feature is the silent shutter that looks like it has a ton of capability. We don't know the actual readout speed, but 1/250 seems like a good guess/estimate. At that speed most of the problems, if not all the problems, of a silent shutter should be solved. I am guessing there will still be a problem or two because they included a mechanical shutter. Maybe they did this just in case as a safety blanket, but I would think there must be one or two things the mechanical shutter does better. The success of this shutter is crucial for the camera, because it will change how many pros work. At weddings, at performances, at many events one can simply taken different pictures if you can go silent. I think a couple of years from now we will think of a silent shutter for these events like many of us think of live view for landscape shooting--we just wouldn't consider a camera without it. Sure we could and did shoot without the feature, but it is just too useful and changes the way we work that it is a must have for any camera purchase.
The silent shutter will also be a boon for many amateurs. Street shooters are going to love it. I think many wildlife shooters will love it too, and combined with the new 100-400 GM this camera will make a very compelling combo for wildlife either as an addition to a Canon system with big glass or as a different way to shoot wildlife. Get closer and don't disturb them. It also will be great for other simple situations. For example, my dad hates having his picture taken. He thwarts almost every effort at doing so, and demands when I get one shot before he sticks his hand in front of the camera to delete whatever shot I got. I have managed a few over the years, but he is a royal pain. A silent shutter would be very helpful to shoot someone like him without him actively trying to ruin the picture. So, I think this camera is getting a lot of buzz and will be a success if the silent shutter works well in most situations.
That said the AF which looks quite improved has to be up to snuff too. I expect it to be better in some ways, but worse in others to DSLRs. It won't match performance and it will depend on what people care most about whether they like it more than, as much as or not nearly as much as Canikon DSLRs. AF and investment will keep the big too in the game for quite some time, but if they don't develop a silent shutter I expect that wedding and event photographers will almost all move away in time.
I also have some thoughts about what I think this all means for upcoming Sony cameras. The first thing to keep in mind is the silent shutter is dependent on readout speed and a high resolution sensor will have a lower readout speed. This very fast silent shutter should not be expected in a higher megapixel camera for a number of years. Sure you can have a 50mp camera or so at 10 fps, but it won't have the readout speed that is necessary for the silent shutter. So for now I don't expect a A9r. Instead expect a A7 III with as Fred suggests a 36mp sensor with on sensor PDAF, and an electronic first curtain. This camera will be a phenomenal value at about $2,000. Sure it won't have an electronic shutter, its AF will be pretty far behind the A9 (but probably only a little, if any, behind the A7r II), and I doubt it will be very capable for video, but it will be a great camera and a great backup for the A9. I expect that camera late this year. Then next year sometime we can expect an A7r III with a new sensor. They could go a lot of ways with this sensor, but I expect high megapixels with deeper wells for high dynamic range. I think 70mp may be optimistic but 60mp and D810 level dynamic range seems quite possible. It won't have a fast silent shutter at those megapixels. It likely will only have modest AF advances, but it will be a killer landscape camera. Expect to pay $3,500 for it. That leaves us with what for me is probably the most exciting release. I expect at the end of next year an A9s with pretty much the A9 sensor, but tuned to video with full sensor readout 8K video. It should be a killer camera for that application. Very high quality including great slo mo capabilities, very minimal rolling shutter, and full frame 35mm at 8K. If you want to know why there is no slog on the A9, I think this is why. They want to use that sensor for a video centric A9s. In time it ought to be a great option. Those four cameras give Sony some pretty great capabilities for a lot of shooters.
Two more points: first, M4/3rds camera will have silent shutters and that will be a very nice boost for them, but they will always be behind in high ISO--I expect when the measurements come in the Em1 II will be about a stop and two third behind the A9. For many of situation in which you want a silent shutter you also want high ISO, so I just don't think M4/3rds cameras will ever be able to quite compete with FF 35mm in exactly the most sensible market for the A9. I say that even though I think the M4/3rds cameras a fantastic in many respects. Second, although this camera will have a hard time challenging for the sports and wildlife market because of lenses that can change fairly quickly. If Sony can bring a 400 f/2.8 to market within a year (and they have had to know they would want want to dod so for at least a couple years) and a 200 f/2 within two years. They will have a lot of capabilities if they make sure these two lenses work with their 1.4X TC and they can update the LAEA3 to work with their 300 f/2.8 and 500 f/4. Within a few years and probably by the time the A9 II comes around they ought to be able to compete pretty well with Canikon even in these markets that aren't there quite yet.