I can't claim the level of scholarship of many of those participating in those threads, but it seems to me that comparing aikido to bushido is comparing apples to oranges. Bushido was a "way", a do, that was reserved for members of a certain social class. It was an ideal whose particulars changed over the centuries, not a static thing, and while certainly not every bushi lived up to its ideals, it would seem nonsensical for a peasant to pursue bushido. Aikido doesn't seem to have any such class connotations.
On the other hand, you could very well argue that what most people consider "Bushido" today was very much a product of the military/government leading up into World War Two and that brand of "Bushido" was very much a product aimed that the general population rather than an elite warrior class. More over, it was during a period when Ueshiba was very much active and he seems to have been as influenced by the times as anyone else (adventures in Mongolia anyone?). Of course after the war it is likely much of that influence was downplayed for obvious reasons.