Another gazillionth re-read. I really love the book, I love the world, the author created, the characters, everything. 
 My favourite things: 
 Tris. The way she thinks about bravery, made me re think some stuff. She is selfless and always willing to stuck for her friends, she is loyal and smart. She comes across as bad-ass, without being bitchy. During the story, you can see her grow from insecure to confident, finding who she is. 
 Four. He is dangerous, moody, ruff at times, but also has a lot of redeeming qualities. One you see his story, why he is, who he is now, you can really understand him. I love how calm and deadly he is, in almost any situation.There is something really charming about him. 
 Side characters. Her friends, family, people she interacts with, are fleshed out, they feel real. The have their own part of the story. 
 World. In future people thought that certain personality traits, ruined world, so they divided world in five faction, corresponding to virtue they cherished: Abnegation (selflessness), Amity (Peace), Candor (honesty), Dauntless (bravery) and Erudite (intelligence). It's very scary world portrait here. 
 Writing. Good book, for me, is the one that pull you in, grippes your attention and doesn't let you go till the end. This is one of those book, that I read (and re-read ) in one sitting. 
 Side note... I really didn't like other two book in the series, so I just read the first one. :)