I for one havent got on the Amex bandwagon yet. For me its the annual fee as well as amex still not as widely accepted.
After reading the forums I am tempted to apply for some but just havent taken the plunge yet.
For me the easiest one so far has been HSBC, applied online and cards arrived a few days later. No payslips or anything needed.
Citi was the second easiest, they asked for payslips, proof of identitiy etc... but didnt need to leave my PC to get the cards.
Depending on where you spend, I suspect you'll find that AMEX is really very widely accepted. While you might not be able to pay at the small shop on the corner, all major supermarkets and petrol stations accept it, as does paypal (which covers off most online shopping, plus you can link Aus Post Billpay to it). Annual fee wise, there are 3 - 4 $0 annual fee cards available, and cards like the platinum edge ($199) and Explorer card ($399) literally pay for themselves, as along with generous points sign on bonus, they include a free return flight (plat edge) or $400 travel credit and lounge access (Explorer).