I think the issue here is that "founding brothers" was presented as if it had already become common usage ("... or as they're calling them today, The Founding Brothers...") when in fact this is not the case. I for one am insulted by this kind of transparent spin-doctoring because it insults my intelligence. Furthermore, recent prize-winning books or not, Founding Fathers is a phrase that is not broken and therefore does not need fixing. The sexual-political motivations of those who promote "Founding Brothers" are clear to the casual observer so I won't belabor the point.