Thers'a rather more common vehicle to lay out philosophical issues, known as an "essay", and somewhere within the vast, elephantine bulk of the novel is a terse, cogent, well-reasoned essay, of about 50 pages or so, just screaming to get out of the literary prison it's currently in. I would have been very interested to read that essay, and I probably wouldn't be nearly as hard on that essay as I am on the novel.
I thought that about Galt's Speech. She should have just admitted to herself that she was developing a philosophy, and that her new philosophy deserved a non-fictional treatise to introduce it to the world. Then the novel that illustrates the sense of life embodied in her philosophy could blossom as a novel.
Plus, I felt that every page could have been 3/4 its actual length with a little bit of softening up of the sentence structure. But I think she prided herself on her precise, excruciatingly grammatically correct use of English. Which I think partially explains why the dialogue is so stilted as well.
Atlas Shrugged is living proof of the truth behind the old saw - basically, if you want to write a novel, write a novel. If, on the other hand, you want to send a message, call Western Union, because the history of attempts to do both in one shot is littered with casualties, Rand being merely one of the more recent. Influential? Certainly, but it's entirely possible to be influential without being a literary masterpiece, as Ayn so ably proves.
As a novel, I did enjoy The Fountainhead more. But I'm surprised that nobody's mentioned We The Living. That was her best novel <ahem> qua novel, IMO. Maybe it's because she was merely trying to illustrate the reality and essential contradiction of the Communist revolution, and she herself had said that she hadn't developed the philosophy of Objectivism when she wrote it. So her sense of life shines through the novel in a much less forced way, and reveals itself to be much more realistic & humane for it.
I suppose you're right about that, though in retrospect I find that it is rather too similar to the "woman trying to pick up the pieces after she finds herself with dead child and cheating husband" genre that seems to dominate the Oprah book list....
Worse, this book was the one for which I was most embarrassed on Rand's behalf. The problem being, of course, that she billed the book as being as close to autobiographical as anything she'd ever write. Thus clumpy, homely young Alissa Rosenbaum (Rand's real name) becomes, as usual, the lithe, beautiful, intelligent, and supremely moral heroine -- and we understand that all of Rand's lithe, beautiful, intelligent, and supremely moral heroines are, in fact, supposed to represent Rand herself. Her icon-loving sister becomes a caricature of later, oozier "mystics of mind." Her father is nice but weak -- another prototype (doesn't he eventually side with the other sister?).
IMO the only arresting character was her love interest, Lev(?), and she apparently lost interest in using him to draw out the complexities of real people. Instead, we see her in later books dissecting the poor fellow. The "good parts" of Lev being lumped into her heroes, and the "bad parts" being packed into her great villains. If anything, the difference between Lev and other characters shows the great extent to which Ms. Rand was willing to subjugate realism to ideological stereotypes.
This points out the greatest weakness of Rand's philosophy. She insisted on placing people on the knife blade of "rational" vs. "irrational," which excludes pretty much all of real human life; and it certainly excludes most of the important aspects of real human interaction. For example, I don't think strict objectivism leaves any room for humor, especially of the Monty Python or Cartoon type. An ideology devoid of humor certainly helps to explain Rand's dark and turgid style -- we are to derive pleasure from the Message, and that alone.