On Fri, Sep 21, 2007 at 02:00:49AM -0400, Chris Ross wrote:
> Rebooting with command: boot
> Boot device: disk0:a  File and args:
> NetBSD IEEE 1275 Bootblock
> Invalid superblock magic

The bootblock is not able to find your root partition somehow.
This would happen, for example, if you had raid0a not start at the
beginning of the raid0 device, or wd0a not at the beginning of wd0.

Martin