We already have this problem, and Google's "search" widgets (e.g. dictionary, snippets, Q&A) are probably a big offender. Falsehoods are everywhere, but people tend to arrive at the truth, and once they do, the truth tends to go viral and flood fill over the falsehoods. What scares me is how easy it would be to create higher-order falsehoods. For example, X, Y, and Z are all false, but corroborate each other, making all of them more believable. These "regions" of falseness already trap millions of people today into throwing away their money -- think pyramid schemes, cults, etc.

I think you're absolutely right that this only going to be exacerbated.