usb1.1 is 12 megabits per second.
usb2 is 480 megabits per second.
remember, there are 8 bits in a byte, so at optimum speed (which never really happens w/ usb for a number of reasons)
you'll get about 1.5 megabyte/s for usb1.1 and 60MB/s for usb2
short answer, don't use usb1.1
if you can upgrade your machine, use usb2...even better would be firewire (aka i.link aka 1394) that doesn't have as high of an optimum speed (400Mb/s vs 480) but it has a higer bandwith.
this means you can use the ipod as an external HD, play songs off itunes and update the ipod at the same time and the transfer only slows down the rate of transfer slightly without affecting the music playback.
if you try to do this with usb2, it'll be choppy, lossy, and might even crash the computer depending on the rest of your hardware.
edit:
you can upgrade laptops by buying a pcmcia card (aka PC card) for either technology (usb2 or firewire), and this is a good method for either apple laptops with a pc card slot or IBM compatibles