I'm not a huge fan of fantasy literature, and I'm not sure exactly what you want as a comment on the new Harry Potter film. I'm confident, though, that fantasy will not fade into oblivion any time soon. In fact, the worse things get, the better fantasy will seem because, by it's very nature fantasy is escape from the realities which surround us.
Harry Potter, of course, and now Twilight, have recently captured the imaginations of young and old alike. In the beginning of each series' popularity, the books were praised as providing opportunities for disinterested readers to connect with literature. It always seemed like more than that to me. I see these as wonderful opportunities to live in a world of "what might be" instead of "what will be." That's the difference, for me, between science fiction and fantasy--the former is often grounded in fear of the future, the latter is a picture of possibilities. And, while there are still "bad guys," the "good guys" may take a beating but they generally win. (Think Lord of the Rings, for example.)
Fantasy is attractive and intruguing and full of adventure; to that extent, there will always be a readership (and market) for this kind of writing. And after the writing, the movies, the amusement park rides, the...well, you get the idea.
I think that the genre of fantasy is going to be more dependent on technology in both process and product. In terms of the former, the more technology advances, the more it will be reflected in the storylines and behaviors of the characters. When the internet was first emerging, movies like "The Matrix" series were able to integrate its growth into their stories and plots. I think that this will continue as social networking and communication become enhanced by technology. It has already become such an ingrained part of our existences that fantasy will not be immune from it. The notion of imagination of new and varied worlds will still have technology as a part of this process. Along these lines, the products of fantasy will also include technology. Recent films like "Avatar" were able to demonstrate new uses of technology and I see this as continuing. The "Harry Potter" sequence relies on technology in order to allow Harry and his fellow Hogwarts to be able to do what they need to do and I see technology as helping to enhance the overall product of fantasy based films, as well.