• Beautiful icon (really)
• Purchase through Amazon, with history, recommendations, etc.
• Book previews available free of charge
• Quick, easy downloads
• WhisperSync between devices
• Text look, legibility, etc.
• Page turning (tap left or right edge of screen)
• Font size options
• Cover art, book jacket info, title page, front matter missing or poorly presented
• Progress through the book (and the length) are very difficult to judge
• Can't (currently) purchase books from within the application
• None of the books, even classics, are free
I'll review some other iPhone book readers soon.