Depends on what he means. He could just mean that he made extra efforts to make sure that his candidate pool for the job wasn't just men.
He could also mean that in a tie for qualifications (between a man and a woman), he would hire the woman; which, while possibly illegal to the letter of the law (in the UK, possibly elsewhere), doesn't seem like a horrible thing. He explicitly states that it's to counter-act male-skewed tech work environments, so presumably if the work place were 50/50 men-to-women, he would relax this preference to women (as a tie-breaker).
I'm not debating whether it's right or wrong. I'm simply pointing out the fact that his approach, even by your suggested guidelines, is still very much illegal in the UK.
Legality to one side, I would be interested in hearing more about this. Surely any hiring decision that's even remotely swayed by gender opposes the entire concept of gender equality?
I question this.
Neither I nor Wikipedia should be used for legal advice, but there are exceptions to discrimination law, and the parent's comment seems to precisely meet one of them:
Assuming absolutely identical skills, experience, education, etc, then you are legally entitled to apply positive action in favouring a woman. Attempting to defend that position in a UK employment tribunal however, would be near impossible.
I'm not sure what the situation is in the US but here in the UK, that element of 'affirmative action' is illegal.