I think they will be both great in a different way. Strategic command seems to me to bring the traditional concept of grand strategy WW2 games to perfection. It takes the best from COS, High Command etc. and (hopefully) will have a challenging AI.
From my guessing, HoI on the other fork of the tongue will be more something like "Axis and Allies meets Europa Universalis". What is very intruiging in this game (for me) is
a) to be able to begin in 1936
to have all theaters of war coveredc) to be able to play every country seperately (e.g. Italy, Poland, even China ...)
Well, the bottom line is that I´m looking forward to both of them.
Straha