After reading the book QED: The Strange Theory of Light and Matter, an adaptation of four lectures Richard Feynman gave at the University of Auckland, I gained a greater understanding of QED. I am not a professional physicist in any capacity, it is just an interest of mine.
However, his lectures were given back in 1979, and the book was published in 1985. Since then, obviously, things have changed, and discoveries have been made.
What things in his book are now different or untrue because of a modern discovery or an advancement in a particular theory?