> I deliberately didn't look at libio, since wide character support is > planned for glibc 2.2. If we switch over after that's implemented we > don't have to carry all the binary compatibility mess.
Implementing pthreads support for the Hurd is an important priority that we would love to have done as soon as anyone volunteers the time to do it. When we have that, we will want to switch to libio because it is thread-safe. When those things are possible, we will want to do them (and necessarily a soname change) without any delay, regardless of other concerns.

