The Internet has been abuzz this week with a column on the psychology of Fanboys. The piece, by David McRaney, basically dives into cognitive dissonance and its conflict with self-perception theory. These are two fairly well established principles, and McRaney is right to apply them here.
The logic is thus: our minds want to reinforce decisions we make, even when we're wrong. Our mind make a posteriori judgments, that is, we explain ourselves to ourselves after the fact. Are you upset that your Alienware laptop only gets 2 hours of battery life, while a MacBook Pro can go hours and hours without a charge? This emotion causes cognitive dissonance. That is, our minds drive us to think that our decisions are good and rational, so when we make a wrong decision, it creates a gap in our logic, a crevasse that must be filled. So, we fill it with illogical thinking.