The thing that bothers me most about Randites, and Libertarians in general, is that they state some things that really seem to be truths, about personal responsibility, the importance of creativity, that the government that governs best governs least, etc. And then they ruin it by making a religion out of it.
To paraphrase Ambassador Spock in Star Trek VI, these things are the beginning of wisdom, not the end. The only thing that really differentiates us from other animals is a feeling of responsibility for the greater good; if we don't have that, we are monkeys, at best.
(Actually, the thing that bothers me most about Ayn Rand is that she was a sociopath. A charismatic one, sure, but still just a human being damaged by her upbringing. Instead of trying to fix herself, she created a religion out of her damaged personality. Which is probably not that uncommon, really.)