To me at least, an important caveat in Ran's initial post is that the mold-breaking course be a tournament course that actually hosts professional tournaments. That caveat--"Harbour Town was a game changer in part because it demonstrated that a tournament course could be a tournament course without looking like a 'championship' course"--disqualifies, at least for now, a lot of the courses being mentioned here. Although I wasn't alive when Harbour Town was built, my understanding is that it acquired its mold-breaking status--and corresponding fame and infamy, depending on the reviewer--precisely because it was in the public eye on a regular basis. We might hate courses built for the professionals (or at least with hosting them on occasion in mind), but we can't dispute their disproportionate influence in shaping the public's view of the game. That is why the USGA's "experiment" with the "brown is beautiful" aesthetic of the last two U.S. Open sites caused so much debate--not because the debate wasn't already happening in inner golf circles (it was), but because the debate wasn't happening in the larger, mostly American, public. But both Pinehurst and Chambers Bay were mold-breaking only with respect to conditioning, not architecture. For the latter, Merion is probably the closest we've come to Harbour Town in the last decade--although Merion, of course, was "new" only because it was really old and, at least to the public, largely forgotten.
So what I think Ran is really getting at is whether any actually new, mold-breaking golf courses might come into the popular consciousness--not just the GCA consciousness--by virtue of hosting one or more professional tournaments. Are any of those already listed in this thread--for example, Tom's reversible design at Forest Dunes, Jim's 18-on-a-9-hole-footprint design--realistic candidates? If not, what would a realistic candidate look like (i.e., what attributes would be necessary to make it truly mold-breaking in the way Harbour Town was)? The discussion has so far focused largely on length, but that seems too narrow to me.