For a substantial part of the population, this happens:
http://www.urbandictionary.com/define.php?term=wiki-hole
If you have ready access to information, you hunger for more, because after you understand one concept or fact, you NOTICE all the other things that depend on that, be they new things building on top or inconsistencies in other fields conflicting with your new knowledge
For an even more substantial part of the population, the "I'll pretend like I know things just because I can look them up in wikipedia or some such source" happens.
I have a pile of physics textbooks sitting nearby but that doesn't make me a qualified physicist. Availability of knowledge isn't worth a thing if it's never been integrated into your mind.
It's less great to think that you know something just because you could swear you have read it on the Internet once, which I think is what GP meant. It's not unusual to see people post bullshit because they think they understand something they've read on Wikipedia or a random blog or forum but actually they know shit about it.