Cyanogen Official, posted an interesting image to their Instagram feed, showing a development board and a touchscreen with the caption "cooking up something new in the labs". Along with the hashtags "EarlyStages" and "TopSecret." Reddit user Endda picked up on the post which then commenced a discussion on Reddit; It is not sure what this board is or the size of the touchscreen, but as you can see from the image, it is at least, legible. It appears to show a device running Android 5.1 and an unofficial CyanogenMod build from earlier this week. The Reddit discussion covered if this was another OnePlus handset or perhaps the recently announced Alcatel Android device. However, neither of these devices are likely possibilities due to both of them running the commercially available Cyanogen OS, rather than CyanogenMod. You can read a discussion of the differences between the various Cyanogens here.
This sort of hardware assembly is the usual way that developers, well, develop and test both applications and operating systems. The development board from the images above cannot be identified and as such, it is impossible to tell what the underlying processor, memory and video hardware is. Although, even if they was known, the board type might still be difficult to identify! It is also not clear what the resolution or DPI setting of the touchscreen is either. Although, it can be seen that there's no on-screen user interface. Indeed, all that can be inferred from this image, is that Cyanogen are developing something and are calling it as in an early stage, not to mention, top secret and likely to have hardware buttons (or perhaps a swipe-to-go-back control?). Does this mean that they are developing a new device, in conjunction with a hardware partner? Or is this simply, that developers are working on releasing CyanogenMod for another device which is not currently supported?
Of these two theories, a new device would seem to be the more likely outcome. From the size of the screen, it might be inferred that this is a smartphone, but from the DPI, it could be a tablet of some description: There really is not enough information to go on. Given that this is described as in the "early stages", the underlying project may not be seeing the light of day for some time.