I think the reason that some may find it Taboo, is because it is supposed to be a private thing, and for some reason, many are embarrassed by talking about it. But not me. To be completely honest, I think bathroom habits in general are rather fascinating, and I see no harm in discussing it. However there is line that I draw that I'm sure others will agree with me on.
I find the posts that talk about the best way to get diarrhea, or the runs, or become incontinent to be disturbing, and the idea of wanting fecal incontinence just disgusts me to no end. Like Chevre said about going into detail, I too don't want to hear how long your turd was, or what it looked like. I could care less if it resembeled Stonewall Jackson, keep that stuff to yourself I say. Those are the only things that I consider to be Taboo on the sublect.
Taking a brown to the Superbowl is a totally naturally occuring thing that no one should be ashamed of discussing. Everyone does it, so there is little reason the topic in general should be Taboo.(besides what I said above.) The only thing I ask is that eveyone use a bit of common sense when dicussing the issue. Use your head, and don't go into so much detail that you disgust people.