Steven Chu of Stanford University and Mark Kasevich of Yale University have managed to separate atomic wave packets by 1 centimetre before recombining them. They saw an interference pattern. According to Percival, that could be interpreted in two ways. They might even spread from one place to another. As yet, however, no one really knows.
Few people believe that a satisfactory theory of quantum gravity is just around the corner.
But now experiments are now becoming possible, things are looking up. Eventually we should narrow in on one true description of the fabric of the Universe. The apple, one might say, has fallen from the tree.