All too often parents look to shift blame. You need to take responsibility for it yourself.
My 12 year old is getting a hell of an attitude problem of late and I think it comes down to a number of factor, but one factor is the amount of screen time he has, which is my fault as I work from home and have been in a busy period for the last few months. So when he bugs to use it, I tend to let him so I can concentrate on work. So we have told him we are cutting his access to the Xbox for a week to see if his attitude changes and seeing what we can do moving forward, working a better schedule, mixing it with further activities and not playing.
He does plenty of other stuff aside from playing games, he does Ice Hockey and Football on a regular basis (in the UK, so Soccer for the American friends) as well as making sure we get out of the flat on a regular basis to get fresh air, go for walsk, etc. But when at home, the Xbox does tend to go on a lot.
It is about balance, but with the Xbox he has been on it way too much of late, which as I said coincides with his change of attitude. However, it could well be where he is hitting his teenage years and what comes naturally with that. But as a resposible (I hope) parent, I will not just be blaming a games console, or a game for anything. I know it comes down to a number of things and have to deal with them accordingly.