Somewhere else recently the topic of originality was covered. I think it was on DesignMatters TV with Laura and Linda Kemshall. Linda stated that it was fine to be inspired by someone else's art but to not limit your inspiration to one piece and one artist only. The danger, like Elizabeth Barton said, is that you end up being derivative. For Linda the key to being unique in your voice is to use a variety of inspiration to make one art piece of your own. You know, this element from that, and this thing from that, etc and then put them together in a way that is all yours.
Beth Berman, who is always looking for creative inspiration, wrote a post on the Fire blog titled Priming the Creative Pump! She refers to a new book she is working her way through. I mention Beth because she lent me another book on creativity named, Steal Like an Artist: 10 things nobody told you about being creative. Here is Austin Kleon, the author's take on being original vs a clone.