No he's not - it's all about treasure, and everyone loves treasure. "Alternate Reality Games" is a term that puts people off.
They love puzzles and stories and treasure - PerplexCity is all these. Season 1: the story is about the disappearance of a fantastical object. Draws on the heritage of Masquerade (which really pissed off the National Trust, who objected to lots of middle class folks digging up England).
But Masquerade had an end.
Talks about the AI game, which many folks found more interesting than the film. One of the first examples of the ARG genre.
PerplexCity players have made a Google Earth-style scrollable map out of the backgrounds of the PC cards. PC has letters to the editor, articles, a newspaper written by players, etc. Giving the cards away for free today, because "they're a bit like crack, really". Some cards have heat-sensitive inks, UV inks, scratch and sniff, microdots, etc.
They do live events too - a conga around Trafalgar Square that got mixed up with an anti-war march ("the police don't like you doing human chains in Trafalgar Square"). Gender split in their players is 50/50, age range is 7 upwards, to pensioners ("the grey crowd").
They've also launched a board game.