I'd just like to point out that despite what you may have heard, postmodernism has little influence in academic philosophy, and nearly all other academic disciplines for that matter (of course it has major influences in some disciplines like English and Anthropology).
The ambiguous (i.e. completely crappy) definition of postmodernism is what makes it so easy to mistake it as having an influence on various discipliens when in fact it doesn't. This, in large part, is what Dawkins refers to when he talks about the lack of content in post-modernism. When something has a really crapass definition it is really easy for non-experts to look like they know what they are talking about by attributing various parts of the definition to some movement/person/line of thought in a discipline.
I cannot emphasize enough, though, that philosophers in general do not take postmodernism seriously, and it has little to no influence outside the fringes of the discipline. I think that people think it does because Wittgensteinian Quietism and, to a lesser extent, Quine's naturalism, seem vaguely postmodern. This is no fault of Wittgenstein or Quine's, though, it is simply by virtue of the fact that Post Modernism has a crappy ambiguous definition.
In fact, I think Mr. Dictator's definition comes the closest to encapsulating what postmodernism is about in practice. There are a few "favorite terms and names" among "coffee shop philosophers", and post-modernism is definitely one of them (a few others are existentialism, deconstructionism, phenomenology, Sartre, Foucault, Voltaire, Kierkegaard, etc.) Why those terms are favored by coffee shop philosophers, I have no idea.