I don't use NetBSD but keep an eye on it, and as far as I know this is where they are at:
http://comments.gmane.org/gmane.os.netbsd.ports.arm/3306
On OpenBSD as well, it is still a work in progress. BeagleBoard will boot kernel and run OpenBSD userland, but there is not yet any support for usb ports or ethernet:
http://www.openbsd.org/beagle.html
This port when done is supposed to also work on PandaBoard but I don't know about BeagleBone.
Brett.