I come from an extremely conservative background. I still have a lot of friends that I care about and keep in touch with from that time in my life. Nearly every single one of them has kids, and nearly every single one of them keeps a mommy blog. They post pictures of their kids, their houses, their pets, their cars. But every now and then a wave of these blogs will go private and lock access. Why? Because they're afraid.
I haven't quite figured out what they're afraid of, and I don't think they know either. In a newspaper article I read on the subject, many women said it's "not safe" but didn't say why or how. (And yet I found blogs linking the article and saying how it convinced them it wasn't safe.) The article said: you put something out there and it's out there. True, this is the internet after all. But there seems to be this growing sense among mommy blogs that the boogeyman is out there just waiting for pictures of their kids. I have yet to find a documented case to support this fear. It also ignores the reality of these safety concerns: posting a picture of your child isn't really that different than taking your child out in public for anyone to see, statistically children are far more likely to encounter danger from people they know than from strangers, and the power of the internet gives nearly anyone the possibility to find out plenty about you whether or not you have a blog.
However, this fear of the boogeyman is getting more attention than the more common problems a blog can create. One blog I read occasionally had a bit of a meltdown. She posted about the birth of her child, which was a crazy story. It would've been no big deal except that they were already in the middle of a medical malpractice lawsuit dealing with that very issue and the lawyers found it along with the blogs of all her friends, and you can bet they'll all be considered as potential evidence. It's not just lawsuits that can lead to blogging trouble. Criticizing a child's teacher could lead to trouble at school. Writing about your job can cause trouble at your current job or your search for a future one. Blogging about parenting may open you up to a mountain of criticism. Applying to adopt or for a job or to attend a school is more and more likely to involve a blog search.
Most mommy blogs are started for the benefit of friends and family. But it's rare that people think through just what it means to start a blog. A mommy blog is no different than any other website. What you post is there for anyone to see. Your pictures can be taken and manipulated, nasty comments can be left, your content can be copied, your name can be googled. Blogging about your work, your friends, or even the school your child attends is something that should be done cautiously. But none of this is any reason to freak. The misguided notion that predators will use your blog as a tool for evil is substituting a serious consideration about how to blog. Just stop and think about what kind of blog you want to have. You should consider whether you post pictures, whether you use names, how searchable your blog is, who you link to and who links to you, the content of your posts, etc. And the same consideration should be given to networking sites like myspace or facebook.
I have no plans to make my blog private, even when I do have kids. It's certainly not a necessity. My personal rule of thumb is not to say anything on my blog that I wouldn't be comfortable saying to a room full of people I don't know, treating it like the public forum it is. There's nothing wrong with going private or staying public, but any blogger should give these matters some serious thought. If you want to know where to start, I'd suggest this BlogHer forum on privacy