I had two machines (ELC, IPX) running 1.4.1 or 1.4.2, and just
upgraded them to 1.5_BETA2.  This didn't require a total reinstall - I
just used the upgrade option (traditional install script), and it went
smoothly.  Note that /etc/rc* has changed and you'll need to
hand-merge that - but it wasn't hard.

However, a lot of my packages broke (eg cvs, missing libraries), and I
pkg_deleted and rebuilt them all.  I think the issue with packages is
that while the old a.out libc is present and a.out binaries get run
fine, a number of packages use libraries that didn't end up with the
a.out versions still there.  So, if you can get ELF packages for the
things you need and have those on-disk before the upgrade, the process
isn't painful.  I did my second system this way after the poor little
ELC spent a few days compiling cvs, perl5, emacs, etc., and the
upgrade/pkg_delete/pkg_add went fine.

        Greg Troxel <gdt@ir.bbn.com>