I only saw the movie; first time I thought it was ok as I thought Meryl Streep was brilliant. Watched it a second time recently and thought it fell pretty flat. Not going to bother with the book!
Haven't read it or seen it... but I suspect I know why it got made into a movie: because it had big roles for women over 40. There are so many great actresses who are no longer ingenues, and so few scripts for them! I guess they're desperate for material.
the one thing that I will say is that a young person out of college without much 'real world' experience may not understand that they don't have to go through all the bs of impressing their boss just to earn their goal.
The only thing that made me finish the book (since I do agree that it was written horribly) was just to finish reading what else happened. I did actually cheer at the end when she told off the boss lady and stood up to her.
I was really disappointed they didn't do this in the movie.