The Mars trilogy was certainly a big contributing factor to my final deconversion. Robinson uses scientific fact, as well as the latest hypothesis on space travel, genetic manipulation, and colonization blueprints to show us a vision of the future of human exploration. What he comes up with is far better than anything NASA has in the works at the moment.
The story of course goes much deeper. Politics, corporate greed, sexual freedom, religion its all here. I very much wish to hear others opinions, and discuss the ideas put forth.