This book is notable (among other things) for the impartiality of its author. As far as I can tell, Burns is the first non-Objectivist scholar to have been granted full access to Rand’s papers. Since she harbors no perceivable agenda beyond relating the important facts about Rand’s life and thought, Goddess of the Market becomes the most “objective” (in the non-Randian sense of the word) account of Rand. Unlike works on Rand published through ARI or by the Brandens, the conclusions of Goddess cannot be questioned on the grounds of bias. “I am less concerned with judgment than with analysis,” Burns writes in her introduction, “a choice Rand would certainly condemn,” she adds with muted irony. I would describe her book as even-handed: wherever Rand conflicted with friends and associates, Burns goes out of her way to give both sides, basing her analysis on the relevant documentary evidence (rather than just on mere speculation or bias). The intellectual conflict Rand had with Rose Wilder Lane, for instance, is fleshed out not merely with reference to letters between the two right-wing individualists, but even with a letter that Lane wrote to a third person describing her final showdown with Rand.
The most interesting revelation in Goddess may very well be the extent to which Isabel Paterson influenced Rand’s philosophy. Rand was still working her way through her Nietzsche phase when she met Paterson in 1941. Paterson reinforced Rand’s growing commitment to “reason” and Aristotle. It is likely that Paterson introduced Rand to the banal phrase “A is A,” which later became such an important mantra within the Objectivist philosophy. Paterson also appears to be the original source of Rand’s detestation of Kant (which would later be reinforced by what she learned from Leonard Peikoff). Paterson may even have been the chief inspiration for Rand’s later fierce moral condemnation of using emotions as a tool of cognition. Paterson, famous for being “difficult” (W. F. Buckley would later describe her as “obstinately vindictive”), once, in Rand’s presence, screamed over the phone at Rose Wilder Lane, because Lane had confessed being led by her feelings, rather than by “reason.” Rand found Paterson’s arguments to Lane “marvelous and unanswerable," and her anger understandable, even honorable. Paterson was providing Rand with a model the younger woman would later imitate, to horrendous effect.
Rand emerges from Burns' book as a talented, energetic, sometimes even brilliant woman torn by paradoxical traits in her character. Rand was a “rationalist philosopher who wrote romantic fiction. For all her fealty to reason, Rand was a woman subject to powerful, even overwhelming emotion…. Her dual career as a novelist and a philosopher let Rand express both her deep-seated need for control and her genuine belief in individualism and independence.” Rand’s life, driven by a “clash between [the] romantic and rational sides” of her character, makes the story of her life “not a tale of triumph, but a tragedy of sorts.”
This book will not please the orthodox champions of Rand who have turned Objectivism into a personality cult. It confirms most of the controversial claims made by Barbara Branden in The Passion of Ayn Rand, including Frank O'Conner's alcoholism, Rand's increasing mental rigidity during her Objectivist period, her difficulties with intellectual interchange, the contempt which Rand periodically felt for her fans, and the catastrophic consequences of her split with the Brandens for the Objectivist movement as a whole. It provides even more light on the possible role which Rand's habitual use of Benzedrine may have had on Rand. Paterson had warned Rand to "Stop taking that Benzedrine, you idiot," but Rand, stubborn and self-willed as usual, refused to listen. It was not unusual for Rand to work on Atlas during the day and then stay up all night talking philosophy with the "Collective" [i.e., the inner circle around Rand, let by the Brandens]. As Burns relates:
The Collective marveled at how the opportunity to talk philosophy rejuvenated [Rand] even after a long day of writing. The obvious was also the unthinkable. To keep up with her younger followers, Rand fed herself a steady stream of amphetamines. 
This opens up the possibility that what some of us find objectionable in Atlas Shrugged—namely, the work's blistering disdain towards anyone who might be so horrid as to disagree with its author, coupled with the book's piercing tendentiousness—may have been influenced by her repeated exposure to these drugs, which can lead to aggression, over-confidence, feelings of superiority, and even paranoia. Following the publication of The Fountainhead, Rand's personal life slowly dissolved into personal tragedy, as she became increasingly difficult and insular. That a woman who would devise an entire philosophy around the notion that human beings are self-creators via "reason" should have relied so heavily on amphetamines is in itself a kind of refutation of her view of human nature.