I love this topic!!
I grew up with a long line of dogs with the name Bear or Lady. I guess they were family names. As we got older and helped name our dogs we had an Angel as well...she was NOT as her name would imply!
Now that I am "grown up" and have my own dogs, I like using human names. I've have had a Sampson, Sadie, Charlie, Tobie and still have a Jackie.