Unless the internet is the parallel universe which contains these worlds, in which case it's a multiverse. Or if each world we visit counts as its own universe, then that too is a multiverse. Since we're getting anal about definitions, though, I'm just gonna point out that the two multiverses thing doesn't really make sense. If there's multiple parallel "real worlds" and "internet worlds" then that is still a single multiverse, even if you cleanly separate internet fantasy land from everyday reality that same divide means you have a multiverse in your hands.