I had been looking into airfares from Australia to Hawaii recently and I thought I should post this following the collapse of Air Australia.
This is more a post for Australians intending to do some shopping while in Hawaii. Although jetstar's basic airfare is cheaper, the price is almost the same if you are upgrading to the same luggage allowance offered by virgin/Hawaiian.
If flying from a city other than Sydney, you will need to book through virgin Australia to take advantage of increased luggage capacity of two pieces of 23 kg each which totals 43kg per passenger. If you book with a connecting flight to Sydney (where Hawaiian departs) flying qantas or jetstar, you will only have the checked in baggage allowance normally offered by these domestic flights - ie. 23 kgs in total for qantas. This is an important consideration if you are booking through sites such as Expedia or webjet.
If flying from Sydney, from what I have read on Hawaiian airlines website, it appears that you can get two pieces of 32kg for a total of 64kg per passenger included in your standard airfare.
If you choose to fly through jetstar, you will need to select your baggage allowance and pay a fee - which can be quite high. However, if you are in Hawaii and end up buying more Han you thought, the excess baggage charges at jetstar check-in will be far more expensive.
I have flown jetstar to Japan before and they were ok. Their basic fares are great if you don't need the extra luggage. However, if you or your family are intending on doing some shopping, it may be worthwhile considering virgin/Hawaiian for their increased checked in baggage allowance, as this may end up being more competitive once you have paid for all the extras.
However, for all the Australians, it seems that alcohol is not free on Hawaiian but can be purchased.