Sorry for responding so late, but I seem to have missed this thread until now.I come down on the side of the show. ASoIaF is a well-written and interesting story but it is NOT as original as Dune nor as artistically significant as LotR. As writers, we find it very interesting because it's a virtuoso performance by a superior technician who substantially invented the form, but I see Martin as a Salieri, not Mozart. I think it will be a case of "Game of What?" in a decade, maybe two at the outside.
This is reflected best in the binge watching phenomena, where people Tivo (or torrent) it until they have the whole season, and then get some popcorn and a free Saturday. It's a good story but it just doesn't have enough drama and (once you figure out he's going to kill anyone who's even slightly nice, along with everyone else) unpredictability to hold out your interest for 3 months, let alone enough to sustain 7 books and 14 years.
Yes, no, maybe?
Anyway, I'm confused. You ask which is better, the show or the books, but then say only that the books are not as original as Dune or as artistically significant as LoTR. Whether these two statements are correct or not, I'm not sure how this makes the show better than the books. You compare it neither to the books nor to other works on TV (or on film).