Recently Rackham have released some information about upcoming releases for AT43 first off they have announced the next race will be the Cogs.
Rackham have some initial art work and the describe the Cogs as.
The civilization designated by this name has not developed as a coherent whole. It is not held together by an sense of belonging. The Cogs do not feel they belong to the same species, race or any other word used by more primative life forms. The Cogs are a relatively loose alliance of four genetic bloodlines. The best and more advanced lineages their original species ever gave birth to. Each bloodline is considered a civilization of its own. They are the closest to what non-cogs generally qualify as a species.”
Slightly reminds me of the Covenant from the Halo Universe where you had multiple races (Grunts Elites etc) forming the Covenant.
AT 43 Cog Concept Art
They have also said that Operation Frostbite will have rules for support units which where mentioned in the initial releases untill now we had no idea when support unit rules would be out.
There is a longer run down at Samurai Gunslinger