Digital cameras are essentially very simple devices. With Single Lens Reflex cameras, the development and body design has been done and everything has been known for decades. The sole new thing is the digital innards and its controls. Pentaprisms have been around for decades, mirrors have been around for decades.
The basic electronics inside cameras are fairly similar. Marketing gurus make an awful lot of noise about insignificant improvements. Saying "our new whizzo M5 image processing engine" is the same as saying "we upgraded our 286 CPU to a 386". The only things that change on a camera are the whizzo CPU (which is not really that exciting), the digital sensor (again not that exciting) and they rearrange the controls and displays just to make it look as though they have done more than they actually have.
Recently the camera mafia brought out a series of new cameras that do away with the requirement for a mirror and a pentaprism. That eliminates a costly mechanical assembly prone to mechanical issues and the pentaprism - a large chunk of carefully ground and mirrored glass. Both of those are prone to manufacturing defects and flaws as well as assembly damage. By eliminating these and using the "live view" that many digital SLRs now possess as well as the digital compact market, manufacturers can slash costs tremendously.
The same smaller cameras also take smaller lenses that contain less raw materials. Because the image is processed by the camera before the user sees it, the image can have all kinds of lens defects cleaned up using onboard software, unbeknownst to the user. This means that less care need be taken with the lenses as the camera can clean up the mess on its own.
So, we have a camera that costs less to produce and which (as most Interchangeable Lens Compacts do) has a smaller sensor. The lenses cost less to produce because they needn't be made as well as their bigger brothers which in themselves were bad copies of 35mm manual focus lenses. The big gripe about autofocus lenses was the cheap and nasty materials used. These have become the norm now and they are as appalling as they were when they first came out. The lack of a depth of field scale is just one criticism. A worse criticism is that they don't stop at infinity - they focus beyond infinity.
Each successive change and development has brought forth ever worse equipment at ever higher prices. Those that suddenly try a manual focus lens are amazed at the clarity of the image. Modern lenses are little better than coke bottle bottoms. The images produced are usually sharpened to death in camera or in post processing. This latest "development" of mirror-less cameras seems to be in the same vein. Junk at high prices.
As an example, a Canon mirror-less camera is $600 (the EOS M) and a Canon camera (with a pentaprism and a mirror) is $399 (the T3). Both have the same size sensor. My question there is, where is the benefit for the consumer? The standard lens (an 18-55) is $139 for the mirror-less camera and $199 for the mirror camera.
I remain completely unconvinced by the change to mirror-less cameras. There is great debate over the size of sensor used in many mirror-less cameras with both Pentax (yes, unbelievably they haven't yet gone bankrupt) and Nikon producing cameras with quite small sensors. The Pentax sensor is the smallest and is on a par with most cellphone sensors. The Nikon is a bit bigger but is still very small. Even the micro four thirds sensor is bigger than the Nikon sensor. It is noticeable that independent lens manufacturers make lenses for the micro four thirds cameras but not for Nikon or Pentax. Perhaps there's something to read into that.
I just don't see the point in spending as much money or more money on a camera that costs less to produce and which isn't as good as the larger camera it replaces. I suppose enough fools will rush in to buy this mirror-less stuff from whichever manufacturer to make it a success when it truly deserves to fail. The innocent will continue to be fleeced by the camera mafia. Time must surely be running out for the camera mafia.