Re: When Nerdom has become popular in the general public
See, my experience is, I know a LOT of people who take great pride in the fact that they have a variety of geek-interests...most of my friends don't LARP, but that has more to do with the fact that nobody in the area runs a game that would interest them to that level and they don't have that much time. But I have several friends who roleplay, and cosplay, and do CCGs/TCGs, and video game...
So, the ranks you describe may be increasingly obscure...but the concept of a hierarchical ranking of them depends on the notion that a large majority of people have a 'well, at least I don't do THAT' mentality, rather than a 'Well, I've never tried that before...let's give it a shot' or 'which of these hobbies are we pursuing tonight?' mentality.
Of course, that could just be me feeling like my experience is the norm, rather than the exception. Most of my friends may have been geeks of one specific flavor or another (a lot of them kinda 'cut their teeth' as Star Trek fans, for instance)...but someone would come along and say, "Hey, we should try this..." And so my social circle consists, in significant measure, of Trekkers who enjoy role playing games, paintball, costuming, computer games, movie-making, SCA-style re-enacting (come are more into Civil War than Middle Ages, but...)
I honestly know barely a handful of people, if even that many, who would fit in this proposed ranking system without repeatedly outranking themselves in one way or another...