I agree with Linnena. As much as we love our pets and their unique personalities, there are way too many pets waiting to be adopted. Besides, there is no gaurantee that the clone will have the same personality and/or live as long (or longer) as the original. You can easily love another pet as much as the last one. And I say this as one who has experienced the loss of several pets, so I know how hard that is.
Well, I know that there are many little ones that need adoption, however I have had one-of-a-kind dogs that I would have loved to have cloned. It wouldn't prevent me from adopting others. We are a home of many well loved and very well taken care of furkids. It might be selfish, but I'd jump at the chance to possibly have another Caesar, Domino, or Simon.
I agree that there are so many dogs that currently need homes. I like the mystery of each personality. It just so happens that God has blessed me with a yorkie that seems to have many of the traits of our long departed standard schnauzer who would have loved to be a lap dog. Can't help think that God brought him back to me in a smaller version. Pepper even looks more like him than a yorkie except that he does have the long yorkie coat. You just never know what pleasant surprises you will get in a rescue.