got it on friday and first thing i see is that when conneting it my work lenovo laptop with core i5 it won't charge. meanwhile the laptop charges all my iphones from 3g to 4 and htc phone
iPads require more power to charge than an iPhone. You might want to check to see if another one of your usb ports on your laptop gives off more power. Otherwise, It's best (and much much faster) to charge via the wall socket.
i only have 2 USB ports on the machine and both are having this problem. i'll have to check the BIOS to see if there is a setting in there i changed along the way
My thinking is that a laptop isn't likely to be able to funnel that much power through the USB ports, since it is a device designed to be primarily run off a rechargeable battery too.