[Al Skierkiewicz]

I believe the current specification is how much current can be delivered to a USB connected device. This relates to the current delivered by the USB host (Chicklet) and you will find similar specifications on USB cards for your computers.
As Jason pointed out, you do not want to draw that much current from the Backup battery so keep your USB devices to a minimum and be careful that each one does not require huge amounts of current. A NiCad battery of this type will maintain a 700maHr rate when discharged at 1/10 C. i.e. 70 ma for at least 10 hours. Between 1/10 C and 1 C that 700maHr rating will fall. At 1 C it is likely 500maHr or less.