1. The name of the commodity: interconnects or dongles
2. The number of them in the "Stack": I agree with Deputy Perks , 6 in, 6 out for 12 total.
Possibly 6 in, and 7 out (dual subwoofers) for a total of 13.
OR possibly 6 in and 5 out (no subwoofers) for a total of 11.
No wait, there would only be 6 since the ICBM would sit below/above a DVD-A player, but the distance from the ICBM to the pre/pro/receiver could be greater (or vice versa).
Ack! Dual subs, so there may be 7.

3. Why they are a "Short Stack": Let's see, a bunch of aging audio geeks looking enviously at a dozen pieces of 12" heavy cable. Obviously, the "short" portion is Freudian (or wishful thinking).

It may also be due to the diminutive size of the unit. Since the ICBM will be basically an active crossover, it shouldn't be too large. Most 5.1 inputs are spaced relatively close, so the "short stack" could refer to a bundle of short interconnects joined together.

Gary