No, they're capped at 5GB/month. Millenicom is different, but you have to pay for a data card there. See previous stories here on Sprint.
Ill have to double check but Have a truck driver that has one and he says it is unlimited but it alos might depend on what cell package you have also.
Nope, not unlimited anymore. It's a recent change.
I'm on Alltel and enjoying my unlimited data.I just hope Verizon doesn't fsck it up, but you know they will.