I don't know, I agree with marmite about being pressured to use it.
From what I've read about Sweden and other Scandinavian/Nordic countries, it seems that there is one way to rear your children, and that includes putting them in day care and going back to work. It's just what's done.
I think if it were free here (and I'm not from the UK) people would question why we weren't using it. And I wouldn't, because I don't want to.
My children will stay home with me until they are three, and then they will go to preschool 6 hours a week. When they're four, they'll go 12 hours a week. They'll enter full time school at 5. (Or six, in the case of my summer-born DS.) This is what I feel is best for them.
Not all children, but mine. There's certainly nothing wrong with full time childcare. Many people don't have a choice, and many people don't want to stay home with their DC, and why should they if they aren't suited to it?
But as someone who worked in a nursery, if I had my choice I'd never send my DC to one. And if the state regulates child care, that's what we'll mostly have, not child minders.
That being said, I think something has to give for parents who have to or want to work.