I agree with the "too much info". Kids at that age are satisfied with just enough. When my sd was 7 I was pregnant with Dagmar and she asked me how did her dad and I get a baby in my belly. I did just what you did, Pebbles! I said "We asked God for one."
She nodded and said, "I'll tell Mommy to do that, too."
One of the few moments (few and far between, but there) where I really liked the kid.
If your kid asked you about some complicated political situation, you'd find a simple answer. I don't know why it's OK to tell kids when they're young that the Civil War was caused by slavery (simple answer), but if you don't want to describe intercourse to them in lurid detail you're a prude. They'll find out soon enough. I personally think too much info could easily make them uncomfortable with their bodies instead of the opposite.