I enjoyed this book. The idea that people would be separated into different factions based on their personality attributes was interesting and I enjoyed the way the author conveyed the idea. At times though the plot seemed predictable and I guessed the true identity of Four long before it was revealed. I also guessed the main plot before it was revealed.
I thought Tris was a little disappointing at times. I felt her attachment to her friends and her good character traits were admirably described. Peter made me mad and I felt myself hoping for a unhappy ending for him thorough-out the entirety of the book.
I enjoyed the action sequences and pace of the book. I will be looking forward to the next in the series.