The trigger may be simplification or sins of omission. People sometimes leave out details because they don't seem important or because they seem obvious from the context, and other people pick on what wasn't said. For example, if you talk about the wonderful possibilities of Sun's Java Virtual Machine, pretty soon someone will accuse you of claiming that Sun invented bytecodes. Yet it is impractical to put a disclaimer saying they didn't on every paragraph. I think many forms of "hype" are of this kind.
Technology can make a difference. I have seen arguments about spelling mistakes and typos. These are rare on Wiki because we can easily correct the original. Technology which suits NoveltyVampire?""s tends to make the problem worse, because it emphasises the new regardless of its value. A frivolous argument about what a particular word means effectively hides the real meat. Wiki's culture of encouraging people to reread a page in its entirity is a strength here.
The problem happens offline as well. The woman makes a suggestion and the man thinks only, "Wow. What gorgeous hooters." At least on the Internet, nobody knows you're a dog. Beavis and Butthead are full of examples. A long, learned exposition about the migratory habits of sperm whales is met with a snicker and, "He said sperm."