Amazing. Just, amazing. It hurt to read Atonement because I didn't want anything to change or for the characters to be hurt. But at the same time, I had to read on and find out how it would end. I had a couple late nights because I just couldn't put the book down. 
 The major strength is the characterisation. Even background characters were given enough detail and depth that they feel like living people. By the end of the first chapter, I felt that I knew these people, that they were my neighbours or possibly even friends. 
 The other major strength was in the realism of the plot. Everything that happens is set up so that the reader knows that there is no possible way that a consequence can be avoided. Yet at the same time, I found myself hoping so much that something wouldn't happen that I would almost convince myself that it couldn't, making it not only surprising but also heartbreaking when the inevitable caught up to the characters. 
 If pressed to find a flaw, I would say that the exposition of the second, third, and fourth parts could have used some work. McEwan seems to want to plunge his readers into a story without a map or compass, making the first couple pages of each part a confusing and difficult read as I tried to figure out who the characters are, where they are, what's going on, etc. This is acceptable at the very start of a novel, but going through it four times was three times too many. It isn't terribly difficult to answer the whos, whats, and wheres in an interesting way and it would certainly help to ease the transition into each portion. As it stood, the start of Part Two had me put the book down until I had the courage to go through all the work of figuring out where the story was. By Part Three, I was more accustomed to McEwan's trick, so I stuck it through. By Part Four, it was still unpleasant, but I was so close to the end and I just had to find out what happened to everyone. 
 It's a fairly quick read, but not a superficial one. Be prepared to devote all your attention to Atonement until the final page is reached. I highly recommend it to anyone, regardless of their interests (though if you love psychology, writing, or history, especially World War II, that would be a bonus).