The internet enables much more niche-targeted interest groups, each with their own micro-celebrities. This means an end to mega stars because we can all indulge our more specific tastes and focus on people who match them better than one-personality-fits-all celebrities. It also changes the definition of "famous", where one person may be famous among their tiny subculture of, say, cereal box art enthusiasts, whose members are spread across the world (and in that sense, "world famous") but utterly unknown elsewhere.
Mokalus of Borg
PS - I guess, if you fracture society enough, everyone is famous.
PPS - But by then, what's the point?