I have heard nothing approaching definite on a release date for a "Volume 3." It would make sense, possibly, to consider the length of time between the releases of Volumes One and Two and quess that it may be similar for a number three.
This is pure speculation on my part, but Fox is releasing Moto Vol 2 (which finishes off that series) in February. Michael Shayne Vol 1 (of 2) gets released in March so Chan Vol 3 would probably be released in Q2 of 2007.
They had been staggering the Chan/Moto releases and so with the latter out of the way I would think the pace of the Chans would pick up.
It is conceivable that 3 Volumes of Chans could be released next year.