The subtitle of this novel is The Tale of an American Dreamer, and reading it is sometimes like reading a dream. As the hotels become grander, the story becomes more fantastical and the prose becomes more dreamlike, until at the end I wasn't sure whether Martin was dreaming, whether I was, or we both were.
The story takes place as the 19th century is becoming the 20th, and Millhauser fills it with reams of particular details. Character development? Not so much. There are few characters in the novel to begin with, and they're barely sketched. Martin's parents, for example, just disappear after a while. The three women with whom Martin is most involved are hardly more than a few gestures and attitudes. But then human character doesn't seem to be the point. The energy of the city (New York, of course), the drive to achieve a dream, the power of the imagination: those are what the book seems to me to be about.
The writing is beautiful, and it's a good thing, because that's what has to carry the book. I wouldn't think this one's for all tastes, but it made a nice change of pace for me.