Work-Around to USB problem?
I spent hours yesterday struggling with the same USB problem others are reporting, using Parallels 3.0. Every time I plugged in my device, I'd get the message that the device was being used by another application (even though it wasn't.) I tried plugging it into one of the USB ports on my keyboard, as well as directly into the Mac. Same problem.
I was about to give up, when, on a whim, I tried plugging it into the OTHER USB port on my keyboard. To my surprise, it worked!
So for some reason, when I plug it into the left-hand keyboard socket, it doesn't work, but the right-hand socket, it does. It seems completely reproduceable. I can't explain it, and it's clearly a bug somewhere - but at least I got things to work. Maybe this will help somebody else.
David