Got home from work and tried both ports on the Wii to no avail. The usb cable has one of those pass-through dongles on the end of the cable, and I figured it wouldn’t matter given that the drive worked fine before without it, and worked fine without it in both lsusb and geexbox, but I decided in the “humour me” department to plug it in through the pass-through connector and voila!
Strange, very strange. But, crisis averted 🙂