A quick check of JI compared to QF taking the last skytrax survey reports from each:
QF SYD-PER-SIN from yesterday. "Sadly both my impression of Qantas was let down on both flights by food of a pretty appalling standard." and "For my next trip to OZ I will be looking for an alternative carrier."
JI SYD-HKT from 2 days ago. "The crew on both flights were attentive, friendly and available in the cabin." and "Overall, for much the same price as a Qantas Economy ticket, you can travel in Star Class in more comfort, with in my view much better service."
Sounds like Jetstar International are off to a good start.