I believe there will never be a backing up of resolution for medium/large format.
I do hope they keep photosite size where it is or at least don't go too much smaller. I wouldn't rule out that it may go bigger, but if so, I would expect by very little. We have customers using digital backs with 9 and 12 micron photosites who can't shoot higher than 50 ISO without gaining unacceptable levels of noise, color artifacting, etc. Of course that is older technology, but other than Canon with the G11/S90, I can't think of anyone who has backed up on resolution.
The resolution issue is so interesting because I hear so often how "who needs so and so many megapixels, stop already". But I've been hearing this ever since the 22MP DB's came out. And yet, the P65+ has been a huge success.
Canon and Nikon will continue to up the megapixel count, and yet when it is discussed as in rumor about the next model, it's usually as a positive "The 1DS-MKIV is supposed to be 32MP's!". There's very little negativity associated with it....yet.
And for sure that is because Canon/Nikon do so much more with their cameras and in ways that more effectively benefit the demands of commercial photography today. So medium format is seen as concentrating too much on megapixels, size of file, etc, rather than making their cameras more flexible and versatile, ala 35mm. But currently, that is one of medium format's few remaining advantages over 35mm. I can guarantee you that a $28,000 6x7, 24MP digital back will fail in the market place. While some may see advantages in the lower resolution, the majority will pass at paying that premium for a product that captures only 2/3 the file size of 35mm.
I agree and believe that medium format has focused on resolution and chip size enhancement (though modestly), but more because other enhancements take a long time. I know they have been working on them. But in the meantime, you can't fault a company for putting out products that people buy and that do produce revenue. They do have to make money while they work on technology that may be 4-6-8 years away. It kind of puts a drain on R&D if you don't have revenue coming in.
Compared to 35mm, medium format has always had the advantage of bigger imaging area, larger image/file size. Those have been their primary advantages. And those advantages were traditionally necessary and a clear reason to choose them. With the changes in the commercial markets, the type of photography being demanded in general (even with wedding, portrait, architecture, etc), the need for speed, flexiblility, maneuverability, and with 35mm now producing (somewhere) in the range of traditional medium format image quality, (and not to mention crimped stills budgets) medium format's big advantages have lost their influence with commercial photographers (though upping it with other markets that value those assets and appreciate the evolution medium format has made from film-based to digital).
So...I expect that we will see more resolution announced this fall, hopefully spread over a larger sensor size, and hopefully progress will have been made on the issues medium format struggles with - usable LCD, in-camera functionality, etc. I see this as a benefit to those in the commercial field (and elsewhere) who still choose to use medium format for its strengths. It helps make that choice to remain with medium format easier, which is a very big plus. For those who don't benefit from medium format's strengths, it probably doesn't matter how improved in terms of "usability" medium format gets because it is, at least for the time being, not the right product for them and that choice has already been made.
We'll see.
Steve Hendrix