Apple tells us that if you’re using both a new iPod (Click Wheel) and an iSight camera on your Mac’s FireWire bus, your Mac may freeze.
The workaround is to either connect your iPod to the Mac via a USB 2.0 port (these new iPods can be synched with USB 2.0 and, like the mini, will also charge over a USB 2.0 connection) or unplug the offending iSight before plugging in your iPod to the FireWire port.