I intentionally mostly stay away from writing about the theoretical and philosophical. Primarily that's due to feeling not qualified enough and desirous of avoiding "religious" arguments. But, I find my mind returning to this topic for no other reason than I like it and it is meaningful to me. So out it spills.
As a practitioner and appreciator of multiple creative arts, I know that a critical element of most artifacts I see as having some kind of value exist at an intersection of the technical and the passionate. In other words, there is a substantial measure of beauty present because the artist has appreciable mastery of both the execution of and the expression within their medium. In other, other words, they can make their instrument do well what they want and show well what they feel.
For further explication I contrast that not with the complete lack of those two, though certainly creations exist that are empty of both. Those are mostly cases of instances that someone should be doing something else. Or, more graciously, they are instances that I have no capacity to appreciate. Rather, it is sadder to me when there is no intersection because the creation is missing one or the other. When the artist is focused solely on the technical execution (listen to how fast I play this complicated musical structure) or the passionate expression (listen to my messy inarticulate anger). The former is cold, the latter a tantrum.
As you appreciate someone's creation, whether a painting, poem, piece of music, film, interface, product, I encourage you to look for these two elements and how they intersect and interact. They certainly will not always be, and do not need to be at all, or maybe should rarely be, in balance. But I have found that both are necessary. And as I create, I try be sure I am practicing both. There is far more satisfaction, I think, in executing expression as well as possible.
Note: Thanks to @semanticwill for adding design-outloud.com to his blog roll. He is an excellent designer (fans of Kayak.com, among others, have him to thank) and thinker. Visitors from there, welcome and thank you! Haven't heard of him? Go see: blog.semanticfoundry.com.