Nathaniel Branden’s book is awful. I thought so when I originally read it, and I was more sympathetic to his style of thought at that time. He goes back and forth between admitting that he was a bastard and blaming Rand for it: the impression one gets from his book is that he believes in free will, except when Rand is involved, where she had a magical power to override it and rid him of responsibility for any immoral actions he committed.
As much as I hated the movie, I wasn’t convinced that Barbara Branden’s book was particularly bad until I read James Vallient’s (sp?) article, “The Passion of Ayn Rand’s Critics.” I would link to it, but it has apparently been taken offline. If you do a google search by title and click on one of the cached pages, there’s an email address where you can apparently ask for a copy of it. (Or maybe buy one, I don’t know.) I wish I had printed it.
Some of Branden’s stuff is interesting reading, mostly for the case studies. But as for theoretical work, I don’t think he’s done anything of significance since his break with Rand.
Last note: without taking a position on what the real deal is with Rand’s personal life – an issue I don’t care about all that much – I will say that “Facets of Ayn Rand” is a charming and inspiring book, well worth picking up. I laughed out loud a bunch of times… anyone who thinks Rand was humorless (how could you, after Francisco???) should definitely read the part where Peikoff accidentally eats a box of fudge intended for her. Actually, I’ll just write it here. It’s that good.
"There’s an amusing story connected with fudge, and it’s an example of her sense of humor. Leonard was fond of the fudge, too. One year, I sent him two pounds, each pound in a separate box – one with her name, one with his. I expected him to deliver a box to her. Well, apparently, he didn’t see the labels. And when he called to thank us, he thanked us for both the pounds. But by the time he called, most of the fudge had been eated by Leonard and some friends. So, I phoned her to report the mishap and to say that I would send her another box. She said something like “Do you mean to tell me that he ate both boxes?” She sounded surprised and somewhat indignant. I said, jokingly, “Ayn, it’s not as if he had just challenged the validity of the Law of Identity!” There was a pause, and then she answered, “Well, it’s not that bad. But it’s close.”