Video Capture Help

Is there any difference in capturing video with a USB cable or firewire? I have a Sony vid cam that has both capabilities. I have only use the USB and was wondering if there would be any difference. I don’t have a lot of experience with video, but would like to do more this year.
Both will give you around the same transmission speed (not that it really matters, since you'd dub it over onto your computer at real-time most likely), but FireWire (or IEEE1394 or i.Link, choose your label) has lower CPU overhead, and thus is preferred when it comes to moving digital video. The higher CPU utilization of USB could result in more dropouts or dropped frames depending upon your computer specs.