But alas, I'm finally back on the Barry project after a few months' detour on other critical issues.
The libusb project has undergone an API redesign over the last few months too. It's all in the devel tree. If you're following libusb, and wondering why things are not being updated, make sure you're looking at the SVN repository, not CVS as its website says. :-)
Since Barry depends on the devel tree of libusb, there has been some porting needed in Barry, and some hacking needed on libusb. The last little while I've been reading through the libusb code, and adding libusb_wait(), libusb_poll(), and libusb_abort() support, which are critical if you want to use async calls and still avoid a threading library.
Still lots of work needed in Barry. It will be nice to have a working libusb and test setup again soon.
[Edited to fix broken link]