The thought has been given...
Use of libusb would require rooting the device and that is not what average Android user would want to do (unless he is an owner of the cheapo tablets, that come rooted already). However, If you look here topic14421.html
, we are already working on drivers supporting ARM based devices. Once those are released, someone may pick the correct binary and use it within Android OS (it is still Linux kernel) and access the device using standard API.