Other than that, I love the story. The plot moves at a good pace. The reader is very quickly introduced to the world that Tris lives in. I especially like the bowls full of the different materials that symbolize the different factions.
Tris's internal conflict is well-written and believable. Everyone can understand being taught something their whole lives and having to decide whether or not they believe it themselves. Her struggle to decide who she really is - Abnegation or Dauntless - is a coming-of-age story that most people can relate to. Also, who doesn't want a test that just tells you exactly what you are good at and where you would fit in?
As far as the other conflict - the war between the factions, I'm not quite sure I understand it now that the underlying reasons were revealed. To me, a leader of Erudite who only wanted more knowledge wouldn't be afraid of an outside world. She would want to know more. (I did read that part pretty late at night, so I may have missed something with her motivations.)
Jeanine does make a pretty good villain, with her willingness to torture teenagers to get what she wants. Also, her ability to turn Caleb against his own sister makes her especially formidable. However, I would still say that Eric is the bigger bad guy of the story. Jeanine is ruthless because she wants something that Tris has. Eric is evil because that is how he likes to be.
I would say that the characters are the best part of the stories. All of the main characters, and even some of the minor ones, are complex and very rounded. Take, for instance, Peter, who is viciously ambitious. You would never expect anything good out of him, but he saves Tris's life. Of course, the motivation for this was that he wanted to pay back what he felt he owed, but even that is an interesting aspect to his character.
And, of course, I really like Four / Tobias. Roth does a good job of writing the romance between him and Tris. My favorite thing about it is that they both see each other as strong, and they treat each other that way. No pity from either towards the other, no coddling.
One of the best scenes is when Four takes Tris with him through his fear landscape. He makes himself completely vulnerable to her, and she accepts him and helps him without it changing her high opinion of him.
I also like that Tris follows her own instincts and does what she thinks is right, even when Tobias disagrees with her. She is completely her own person.
Overall, a great story and a fun read.