Something doesn't make sense here. Shouldn't these two error messages be
the same:
  sirius:/usr$ ldd bin sbin
  bin:
  bin: Permission denied
  bin: exit status 1
  ldd: sbin: read error: Operation not supported by device

The directories look identical to me.
  sirius:/usr$ ls -ldo bin sbin
  drwxr-xr-x  2 root  wheel  - 6656 Dec 25 11:58 bin
  drwxr-xr-x  2 root  wheel  - 4096 Dec 25 11:58 sbin

What am I missing? Or is my filesystem just trashed?

Cheers,
Jared