We are probably more open than we should be, but it is clear we have to be careful.
My mom knows what my husband makes, and we are fully open about money discussions. We can do this because she is also pretty clear that she isn't helping us with anything, so there's no judging to be done. It's my life to live (or mess up).
I have a friend who is very tight lipped about what her husband makes (actually, she doesn't mind, but he won't let her tell anyone). I think it's for the best. It is entirely possible that with both of our husbands having the same degrees from the same college, they could be making 25% difference on salaries. I'm glad we don't know honestly, but since we talk about other financial details, I'll be able to make a good guess when she finally goes and finds out how much of a mortgage they can get, but I will not let her know that I made a guess.
We have another friend who we are close to who knows what my husband makes. I mentioned that we are planning to apply for financial aid for my older son applying to an expensive private school and he was upset because he knew that my husband was making a lot more than him. I found it really awkward. Whenever I talk to school moms about it, they always say "Just apply and see," so I was not expecting his reaction. :/
I have another friend who I am close to. We worked for the same company, and she knew what I made going in which probably helped her to get a higher salary--knowing what was reasonable to ask for and to accept. We also know approximately what our respective husbands make which has a big disparity, and we are both in high COL areas, but she bought a house first, so I hope she doesn't feel bad. When I finally buy a house, it'll be crappier than hers, so I don't think she has anything to feel bad about. :)
I think talking about net-worth is ok, but not with your kids. My parents talk to me a lot about what I'll inherit when they die, and I find it VERY VERY awkward and difficult since I could really use that money now, and I don't want to be wishing for anyone's early demise. I've wanted to ask them to stop talking about it, but I've come to realize that they're trying to offer me a gift but they can't give it to me yet, and I need to find a way to thank them and express my gratitude while they're still alive without making it sound like I'm looking forward to them dying or anything. I'm not quite sure how to do that. The irony here, though, is that since I'm open about our finances with my mom, she knows what I'd spend the money on when she dies (a house in a high COL area), and she doesn't really approve. I told her she's free to put it in a trust if she cares, but she doesn't want to do that.