@TA: ^ We do agree that it's a cultural issue. I just think it's a cultural problem that should change. It's not unfair in the sense that an evil boss discriminating against their employees is unfair, but it is still a form of culturally ingrained inequality that tends to pressure people into different life paths depending on their gender, leading to power imbalances and other unequal outcomes in society as a whole, not to mention, I think, less personal freedom for self-expression and self-determination.
I wouldn't say a woman has "an equal opportunity" to have a man stay at home, since most men probably wouldn't be as enthusiastic about that; men who do choose to stay at home, for example, often report being criticized for this by male relatives and friends, and naturally we have few unambiguously positive images of stay-at-home dads in our culture. On the flip side, a man who does want to stay home with kids anyway wouldn't have an equal opportunity to do so because it'll be harder for him to find a partner willing to be the primary breadwinner, since women are taught from a young age that they're expected to be the primary care-givers, and many wouldn't be willing to give that up. As the attorneys in your office demonstrate, there are exceptions, but the cultural trends are still there.
I think actually more regard for work-life balance in society in general would go a long way towards fixing this, since such a shift would give both men and women more opportunity to balance work and family life, hopefully leading to more sharing of roles and less rigid gender stereotypes.
Dorjan: I think notjarvis replied to you pretty well, but I'd also reiterate that I'm not sure why you think your one example is proof; it's a single data point. There's a tendency on these forums (or maybe it's general to the internet?) to look at personal stories as iron-bound proof for some reason. I look forward to the next politics debate where I can simply say "I spent my childhood in Soviet Russia!" and win the argument right there.

In your case it seems (based on what you've said) your wife wanted to stay home with kids much more than you did; you say this has nothing to do with culture but, as notjarvis argued, that's not necessarily true. If you want to argue that men just can't care about their kids or be as close to them as women, I think you'll find quite a few people willing to disagree with you based on
their personal life experiences. Your case may also well be atypical, if only because in most cases, men tend to earn more than their female partners (as the average income numbers I brought up earlier suggest), making it even more likely the woman will be the one to stay home, and leading to a sort of a cycle where we continue to see women as the "natural" primary care-givers.
I think the main issue, really, is that most people say "free choice" and I see "cultural bias." Most people would argue that if you choose to go along with a biased culture it's still your decision, in the end, so there's no real problem to be fixed, but I'd argue that cultural pressure constrains our choices, makes it harder to go against the grain, and in the end, harms us all, both male and female.
Edit: I've been ninja'd by... a bunch of people. I wrote this after reading TA's last post.
Dorjan, if you feel that your one example isn't proof after all, why do you feel it means that I am wrong? ("I have to argue here. You're not in the position to speak about this with personal experience I guess? I'll give you a real example..." You're clearly offering your example as a counter-argument, not to mention saying I'm wrong because I haven't had a comparable experience).