Personally I never use this term over the Internet, let alone in the open, what doesn't change the fact that some people simply overreact. This entire thread is an overreaction. Few posters have used the term 'Jap' or 'Japs' in the threads over the Shogun section, so what? Did they use it to insult the Japanese? Was it out of malice?
Ignorance, what kind of ignorance? You know what I call ignorance and lack of being civilised? I will tell you! That is being so centric of your own culture, that you can't stand someone over the internet doesn't feel like an offended Japanese individual, and not everyone is, frankly. I can understand the older generation to be annoyed by the use of this word, but the younger generation has nothing to back it up, besides obvious national pride, that is somehow even more prevalent since the end of WW2 and financial crisis from the past two decades.
But that again, is history ... and this is Internet. A 'Jap' in someone's post is not the same as 'Hi, Jap' in front of Japanese person. The latter might be a grave insult, unless addressed to a Japanese friend (then it would be most likely a joke or little tease, if anything ... but certainly not out of malice or ignorance). I can't see how a person which isn't Japanese might feel offended by the use of word 'Jap', if anything the person might be disgusted.
'Hey, do you see this Jap over there? Let's ask him about this place, we are lost' =/= 'Looking for a fight,

ing Jap? I will show you a nuclear punch in the face!'.
The above is all to be said about this thread, really. You overreact, even if your concern is valid.