Yes - the price they quote is the price you pay. And note, I did say this is a recent change. I found myself flying Virgin Blue a hell of a lot when I first arrived here, but now it's Jetstar 90$ of the time.
I'm flying a lot and my choice is nearly always based on cost alone, such is my budget.
Jetstar are cheaper, which is a shame because I have a lot more fun flying with Virgin Blue as it's more informal, but that's not a good enough reason to pay more.