Well, FOF has been out longer than COG:EE, so it has more posts partly for that reason, but it is the more popular game of the two, as you rightly suspect. I'd attribute this simply to the Civil War being more popular than Napoleonics. That's an interesting question about the ratios of forum posts and sales, and now you've got me curious. I'll have to ask EricBabe, who keeps track of our sales figures. I can't promise that I'll be able to share the answer, though.
We very much would like to do a FOF2, but it's going to have to wait since -- and it seems appropriate to divulge this information on the anniversary of the shelling of Fort Sumter -- we will first be producing a series of releases using a greatly modified version of the FOF tactical engine for historical battles, starting with 1st Bull Run and a few other early battles. More on this soon...