What are the pros and cons of single sex education?

I spent a year in a boys’ school when I was fifteen. I am told that the school is starting to go coed for the oldest kids. I have mixed feeling about this. When I was a kid, I thought single-sex education was ridiculous, but it didn’t really bother me.

The school says that they are going coed for “social” reasons. I suppose socialization is part of education; as is learning how to deal with girls. Although, looking at the questions here, I’m not sure coed education does a better job.

The school did a poll of former students, and found that it was the younger former students who wanted to remain single-sex, and older ones who wanted to change. I’m an older one, but I like the idea of a single sex school, although I don’t know why.

What are your thoughts?