Defective Yeti gets all, like, defensive about "like":

In truth, like has a fairly well-defined a widely understood meaning when used in conversation. It signals that the facts being related are guesswork and hyperbole, or that the dialogue being recounted is a paraphrase at best. It serves as a warning to the listener: Caveat Emptor.

Really, "like" is more than just a word -- it is practically a auxiliary verb that puts the entire statement into a new tense. Call it the "Past Approximate." If someone tells you they once ate fourteen eggs in one sitting, you recognize that is a boast; if someone says they ate, like, fourteen eggs, you know instinctively that the number was probably closer to five.