Just a few days ago Sony announced their follow-up to the a7 line of cameras, by listing the a7ii, with full specs, in their Japan website. Info is now available on the official mini-site.
Sony somehow managed to keep leaks about this camera under tight control; in fact none of the rumor sites had any valid information on it at all.
The camera represents a somewhat incremental upgrade to the basic a7, introduced more than a year ago, offering a number of usability and performance improvements; with the exception of one new feature which has the photographic world in general, and Sony fans in particular, on their heels: 5-way in body image stabilization.
In case you've lived under a rock during the last 3 years, you already know Olympus has one exactly same system in their O-MD and Pen series of cameras. And, if you haven't used it, you really don't know what a gamechanger this is.
Sony, mysteriously, claims it's their own proprietary design. Right. They have 25% share of Olympus, have been exchanging tech for some time now, and still they decided to develop the same technology from scratch. Seems legit.
In any case, Sony certainly made the system work with a full frame sensor (which was deemed very difficult to do initially) and even went one step further by allowing the combination of in-camera and lens-based stabilization. Which brings us to the discussion about Sony being the "new Kodak" and the One Beautiful System.
Back on film-camera days, any photographer had access to the same "sensor" as any other photographer. Usually made by Kodak, with Fujifilm and others trying hard for a small slice of the pie. What old-time photographers couldn't easily have was access to lenses others than their selected system. Because the recording medium was the same, any difference in technical accomplishment was down to lenses and a number of secondary camera characteristics; but mainly lenses. The trouble was, one system could have, say, great standard and wide lenses, but mediocre telephotos; while another one excelled on telephotos but was weak at super-wide primes. There was no practical way to adapt lenses from different systems; and let's not forget that, particularly in 35mm photography, there were dozens of companies active at that time. Some attempts, such as the Tamron Adaptall system were interesting but, ultimately, unsuccessful.
I believe the new Sonys will be the closest to the "One Beautiful System" one can hope to achieve. As we all know, their sensors are already in almost all other makers cameras, in some cases, exclusively. They are "Kodak" in this department, already. On the other hand, presently, tens of thousands of mirrorless photographers have adapted legacy lenses on their cameras, but it's the first time this gets practically possible for full frame cameras, where old 35mm format lenses retain their stated focal length and don't crop. There are literally thousands of older lenses capable of adapting, plus a number of them can also autofocus with the use of proper adapters (apart from the "family" Minolta/Sony Alpha lenses, most notably, Canon and Contax G-system lenses).
If we'd try to be mean, we could say this is a great way for Sony to compensate for lack of native glass. Truth be told, the FE-system is far from mature. Besides the obvious sparse lens selection, we'll have to see if Sony addressed some of the more serious shortcomings of the first generation a7. Autofocus is said to be faster, but it remains to be seen if it can compete with DSLRs or even other mirrorless systems. In their spec list it states AF as being sensitive to -1EV, which is fairly ridiculous, but we'll see. Far more important, has Sony changed the 11-bit "lossy" RAW compression algorithm they used for the first generation, which resulted in their IQ potentially being inferior to Nikons using the same sensors? What about the ultra-loud shutter? There is a number of questions which will be answered as soon as the first production cameras are available for review.
All said, the second generation a7 looks like the opening battle cry on the final assault of mirrorless against the dying DSLR breed. More will follow from Sony; it's almost certain they will also introduce a "pro" level (a9 ?) line of cameras in January '15.
Interesting times, indeed.