I liked the film, although I found it kind of sappy...but that's okay.
As to the nature vs. nuture debate, we have A LOT of very affluent people in my town, good Christian upbringing, and there have been kids who were caught driving into Chicago to buy heroin to sell out here.
There are drug problems and crime committed by the affluent as well as the poor. I have met some pretty unsavory young people here...the lack of civility and the coldness emitted from them was frightening...
It comes down to many factors, genetics, environment, whether you had an illness that might have altered your brain chemistry...so many things can influence how we turn out...
The Blindside showed how reaching out can transform your own life...at least that's the message I got from the film...