Now that Georgetown is gone, and is essentially irrelevant to us, it makes sense that some fans can move on, especially the younger generation like myself.
We have hated Pitt for a long time, and now that Georgetown is gone, an old rival steps to the forefront for those living in the now and moving forwards.
The Pitt rivalry is going to grow and the hatred between the two fanbases has clearly kicked up a notch this year alone. Louisville coming in next year is going to re-spark that rivalry especially if we happen to meet in the NCAAs. With a second Duke game poised to take place, if it is even half as awesome as the game at the Dome, it will start sparks flying in that soon to be rivalry as well.
The old Big East is dead, and so are it's rivalries, but we are in a new place and with it comes new rivalries, with new fanbases to hate. That doesn't mean the past never happened, and that the Hoya's aren't still the devil, just that if you don't hate them as much today as Duke, it just speaks to their overall irrelevance to us as we go forward. We might play them from time to time, and when we do the sparks will fly, but for the vast majority of people from my generation (or the next I suppose) the Gtown rivalry is in the past, and the next set of ACC rivalries will either be intensified or start anew.