Various codenames have been flying around the BlackBerry 10 project for quite some time, and Colt is one of the earlier examples — we heard about it as a QNX device way back in August, but then later got word that it may have been canceled after the eventual renaming of BBX to BlackBerry 10. All bets are off, then, as to what the leak of mockup images at N4BB alleging to show the Colt device running a Facebook app could mean.
The renders don't give away a lot of detail, but the device itself looks to be a standard touchscreen slab with no physical keyboard, and it matches previous images from a leaked presentation fairly closely. The Facebook app shows how it hooks into BlackBerry 10's sharing interface, and the app itself seems like it could have some additional functionality over other versions: you can select image upload quality, for example. It's difficult to place too much stock in the veracity of these images, especially considering BlackBerry 10's recent delay to early 2013, but the pieces could be slowly falling into place.