Some see this as a political issue. I don't. School systems haven't known what to do with NCLB and haven't done a good job of administering the requirements of it. It's inevitable, I think, that as more people discover that schools are sharing their information, some will choose to opt out. As schools develop their opt out systems, easier access to opting-out will increase the number as well. Not every opt-out (or even the majority) represents a Cindy Sheehan.
I don't think this will have a big impact on recruiting. Children of parents who don't want them to join the armed forces aren't likely to be great candidates while they are still in high school and living at home. Those under 18 would need their parents permission to joint anyway. I remember when I went through the MEPS station, one of the first questions was "Who here is 17 years old?"
As a matter of principle, I support parents' rights. If I don't want my children talking to someone, doggone, they'd better stay away from my kids.
As a matter of both principle and utility, I favor recruits that are both informed and true volunteers. For the youngest recruits, it's also important to have parental support. I spent three years working with basic trainees and know what a pain it is trying to work with recruits that don't meet those specifications. Those who don't complete their enlistment are terribly expensive and hurt readiness.
So, although the anti-war types want to make this an anti-war issue, I think we all should be saying, "Sure, the law provides for parental opt-out. If you don't want to get the facts before you make up your mind, feel free to fill out the form. We'll leave you alone."