Dedicated Pentax fans will probably already be aware of this but for those that don't know there are strong signals that Pentax will release their first ever full frame DSLR in October this year. Up to this point all Pentax DSLRs (not counting the mid-format 645 variant) have been APS-C half frame cameras.
The various photography forums including DPREVIEW, PentaxForums, and Imaging-Resource have all kinds of guesses going around about what the specifications of the new full frame Pentax are likely to be.
One consistent line of thinking is that the full frame Pentax will use the new Sony 36MP high dynamic range sensor. If this ends up being the case this will make the new camera from Pentax very interesting. However there will be a downside for many current Pentax DSLR owners; they will need to acquire full frame lenses to take advantage of the full frame sensor.
Also a 36MP sensor will require very fast processing if the camera is going to provide the continuous shooting speeds currently provided by the APS-C format K-3.
It will also probably need a newer larger battery capacity than Pentax have used across their last three flagship models (K-7, K-5, and K-3)—unless they have some high-tech tricks they can use to cut down battery drain in a full frame model.
The announcement by Pentax does say that the new camera will work with all existing DA (half frame) lenses but this will require cropping in most cases (if not all). Most likely the camera's logic can be switched to only sample an APS-C sized part in the middle of the sensor. This being the case this would speed up processing and continuous shooting when using a DA lens.
It is possible that the DA mode in the new camera might even be smart enough to tailor the cropping for individual DA lenses; based on testing carried out by Pentax to see what the optimum cropping is.
There is another line of thinking that the new camera may not actually be a DSLR; that it might be mirror-less camera with a live viewfinder. However the mock-up images that are around the Web seem to indicated a DSLR format based on the apparent size and shape of the camera body.
As can be seen in the picture above the body style shown still has the prism housing at the top indicating a DSLR.
There has been a degree of criticism from the Pentax community (sometimes referred to as "Pentaxians") over the last three years or so complaining that Pentax have not put out a full frame camera. In response to this Pentax has responded that they wanted to wait until they could provide their target group with the very best technology on offer at the right price. If they had released a full frame camera three years ago the price of that camera would have been way out of Pentax's target group range; up in the $3,500+ area. However now in 2015 the technology and the prices are right for Pentax to produce the quality of camera they want and put it in the market at the right price for their target group.
Based on the above it almost sounds as if we can expect the new full frame Pentax body-only to come in under AU$2,000 and maybe even close to the AU$1,500 mark.
As to what the model number will be we can only guess. The main guesses around the Web are K-1 (following the K-7, K-5, K-3, numbering), or maybe KF-7 (i.e., start a new KF series and then begin with 7 and then do a KF-5, KF-3, etc., for better models over the years), and F-7 (but Nikon sort of owns model numbers starting with "F").
If I find out more I will post it, but it sounds like us Pentaxians might need to start up a savings fund to mature in late October or early November.