Do keep in mind that PR is something different than marketing or advertisement. Those people running around, dropping names and 'generating spin'? That's just a very tiny part of PR. PR is about shaping the public opinion, not just one person's mind.
On a side note, I wrote my thesis on wartime propaganda. I found out that the strongest motivator for people to take action is fear. The fear of losing something, missing out, or a common enemy (think Apple-Android!) is very powerful.
On a second side note, I read another comment about lying. Lying isn't right of course, but there are several degrees of lying. And imagine if know how to sell a lie, how easy it would be to sell righteous truth...
Drop me a line if you need some help or advice. I'm by no means an expert on PR in Silicon Valley, but I know a thing or two about PR.