According to german sites TecChannel.de and Golem.de Microsoft has now made drivers available to support USB 2.0 devices under Windows XP. USB 2.0 supports transfer rates up to 480 MBit/s and is downwards compatible to the older USB 1.1 interface. Apparently the new drivers are to download via WindowsUpdate. You will probably need to have USB devices installed for the driver update to be shown.