Almost every oneworld airline that I've flown (BA, QF, CX, EI) has extended some special courtesy at one point or another. Some examples include: BA upgraded my wife and I to first class LHR-TLV on award tickets, QF upgraded me OOL-SYD, aboard CX HKG-ICN I was visted by the flight's purser twice to check in on how I was doing (and he visited nobody else in the Y cabin as far as I could tell). I have redeemed OneWorld awards twice from AA (including an RTW), and flown on two paid OW Explorers.
oneworld has been very very good to me. I would love to see them add more carriers, especially in Asia/Pacific.