The book is very well written, and is very realistic.
Sex: Young couples attempt to several times, but it is never explicit (pause)
Violence: Pepper Spray against protesters, a stabbing (non graphic), a waterboarding (torture) session. General cruelty from the government towards minors (PAUSE)
Drugs/alcohol: The main characters host a party with alcohol at it. The main character says he has a fondness for hash. (PAUSE)
Social Behavior: The government is cruel, and treats everyone like a terrorist. The main characters are hackers, and hacking is shown as a good thing (however, I would like to point out that hacking has gotten a much worse rap than it should, it is not as dangerous as it is. If more people knew how to hack, there would be LESS identity theft, because the security would have to be better). (PAUSE)
All in all very good Mature: 13+, Normal: 14+