The question of whether or not games are art isn't one that can be resolved simply by providing a definition for art which encompasses gaming. For one thing, you would need that definition to be broadly accepted in order for your argument to be broadly accepted.
So it's refreshing to read an article that doesn't try to resolve the question but rather frames it within the context of established theory. We didn't all study philosophy of art so this article was highly informative, to me at least.
Oh, and a huge +1 to the final conclusion. For the art of gaming to evolve, it desperately needs to be more accessible to would-be creators. Developers should waste less time making their own bland, generic content and put more effort into empowering users to show them how it should be done.