By saturation time in a decade or two, there could be a billion users. Language problems will be only a minor barrier by then. Programs for crude translation already flourish on the Net. This cornucopia of contact will need a new generation of filters, and something better than filters. But even the best filter is inherently passive.
None can fulfill the higher functions of helping to generate the quality material most readers want.
Think of trying to find a discourse on, say, the cultural impact of the Beatles. And you wouldn't mind reading some adult nostalgic reflection on the Fab Four yourself. Then you set separate vocabulary levels for both of you, which winnows down the fare to perhaps a few dozen sites. She won't want to see analysis that compares the Beatles with the Kinks, say, but you might, so you tailor your list for that. By this time you're facing two customized sets of choices, probably only a handful of potential sources.