Yes we want to know. We found out with both the girls, and of course they want to know too! I get alot of people asking them whether they want a brother or a sister like they actually have a choice iyswim. Better to tell them (esp. Dd1 who is Autistic) and let them get used to the idea of boy/girl before baby arrives.
I guess its about 50/50. Some people do not want to know, but I have heard of sonographers letting it slip!!
They are wrong occasionally, so I say its likely it will be rather than it definitely is. The only way to tell for certain is through amnio test as far as I know.
I knew what my two were without being told (women's instinct?) Just had a feeling that Chris was a boy and when I was expecting Amy at my 20 week scan I asked the sonographer "How's she doing?" and she said "Oh you know you're having a girl then?" and I said "No but I had a feeling she'd be coming into our lives".
Every scan I had, Amy was turned away and we could only see her spine so it was quite freaky that I knew she'd be a girl lol!
When i had my first one (he is now 33) mums to be didn't even get a scan. I was convinced he was a girl and when he was born and I was rather off it having been sick and had lots of pethidine I remember saying to the midwifes can you sure it's not a girl