This is exactly why I love the microSD card, I use it all the time with a microSD card adapter to transfer files to and from my Android phones.
It really sucks that the Nexus S does not have a microSD card slot. This means more issues like this pop up for users.
Windows does not have the most reliable USB management process either. A fair bit of the time my PCs don't recognize USB devices, and I have to remove and replug in, or try restarting windows and then try to plug in again to get the PCs to recognize properly. This is just the annoyance of USB interface.
I advise you just get a microSD card adapter and a 8 or 16GB microSD card to put your music and files on it and be done with it. That way there are no drivers to install, no software to install, no questionable USB cables to mess with.
microSD card works the best, by far.