I remember an article in some computer magazine about the whole USB2.0 update.
to keep it "easy" for consumers, they decided that everything with a USB plug would be called "USB2.0 compliant". this is true because usb2.0 is backwards compatible to usb1.0 and usb1.1. However, to keep the difference "clear", they introduced "USB2.0 full-speed" and "USB2.0 Hi-speed"
"full-speed" is what they used to call USB1.1 and has a transfer rate of 12Mbit/s
"Hi-speed" is true USB2.0 and has a transfer of 480Mbit/s.
So, in a very strange way, the S1 player is USB2.0 compliant, and to be more exact: USB2.0 full-speed compliant, which is actually USB1.1 with a new fancy, markiting-wise very handy, name
(for more info: http://www.everythingusb.com/usb2/faq.htm)