I just read a very compelling blog post from Scott Hanselman where he quoted colleague Erik Meijer as follows:
Simply put, you cannot go into a site and look at their source and see a pretty formatted version of the markup. My question to you is similar to what Hanselman asks: is that important to you? If it works, is that good enough? In my opinion, YES - results are what matters - Google is an example of that. But I must admit, as a developer, it is nice to have the ability to, once in a while, look at the source and get ideas and examples from sites I admire.