I got Captain Jack at 7 weeks, but he didn't come from a breeder(he was a "happy accident") and he was much better off with me. The lady he came from didn't know anything about puppies so at 7 weeks he was covered in fleas and had never been treated for worms! He has been a bit of a biter!
Junie B came to us at 14 weeks... it seems to be taking her a little longer to bond with us, but I'm not sure if that is because of her age or if it is because she is too busy playing with Captain Jack! Captain Jack knew that I was his new mommy the first day, Junie B has been with us for a week and is just now getting adjusted. I think that 10-12 weeks would probably be a happy medium!