I read an article last weekend that I found particularly interesting. I found the article on Design Observer, a website that has regular postings about design concepts, graphic design, and other miscellaneous topics.
The article discusses art that occurs within a given template. When this art occurs within the template, the question is: Where is the creative act situated? Is it in making the work? Or is it in making the rules? Here is the link to the article.
One of the examples that is discussed by the article is the album artwork on Beck's newest release, The Information. I don't have the CD but my understanding is that the cover is blank and that the CD comes with a set of stickers so that you can design your own album cover. You can go to the this website to see the album artwork that has been created by people and uploaded to the web.
Not sure if my answer to the question would be considered a cop out, but I would say that the creative act is situated in both places and that it is simply the nature of the creative act that changes depending on what actor you are discussing. One actor has less constraints than the other and defines the template in such a way to inspire creativity. The other actor is more tightly bound by constraints and responds to the template. Just because you are bound by a template and rules when you create something, it does not mean you are not being creative.