The cyclic nature of most industries is most prevalent in aviation. The good times have been going for a while now so just wait for the correction in global markets. The first carriers to be hit will be the LCC's.
On another note, recently a lady I know who works with a charity that deals with the balinese was very livid with JQ. First trip on JQ and had 100kg of goods with her up to DPS to give to the locals and JQ charged her a fortune. Previously she had an arrangement with QF who were a bit more accomodating. I dare say that when JQ have a bit more direct competition, consumer discretion will have a negative impact on their business.