I would actually refrain from following up from customers once the item has been delivered. They might consider it spam.
The most I do is when a person buys something, in the automatic notes i have a little thing saying, "If you love the item, feel free to come back and leave a review."
Beyond that, there is really nothing else we can do. Like BeaG said, we can beg for reviews. Just hope that they do come back and leave one.