Status as of Octave version 2.0.16/2.1.31

Interface compatibility changes
===============================
lin2mu.m        (defaults to -1:1 audio range)
mu2lin.m	(defaults to -1:1 audio range)

Interface compatibility extensions
==================================
contour.m       (default number of contours)
__pltopt1__.m   (accepts line types)
cross.m		(accepts matrices)
deblank.m	(accepts matrices, better \0 handling)
fftfilt.m	(accepts matrices)
freqz.m		(lots of changes)
imagesc.m	(only display if not returning scaled image)
polyder.m       (accepts a*b, a/b)
polyderiv.m     (accepts a*b, a/b)
polygcd.m	(new function for auto-reduction on polyder)
rand.cc         (accepts "state" argument; use MT)
MersenneTwister.h (long period random number generator)

Interface extensions
====================
grid.m          (control x/y grids and grid density independently)

Bug fixes
=========
tf2zp.m         (don't remember)
zp2tf.m         (don't remember)

Speedups
========
findstr.m
hankel.m
hilb.m
index.m
invhilb.m
kron.m
rindex.m
toeplitz.m
vander.m