Two updates in one day? Well, whilst playing around with the class today I just had a few more ideas how to make it more useful, so I quickly implemented them:
I've added a blend() method which allows to blend between two ColorMatrices - this makes color tweening very easy because you just have to tween one value - the amount of blending.
Additionally I've added a "filter" property which returns a ColorMatrixFilter object initialized with the matrix values - this saves you one step.
Furthermore there's now a randomize() and a clone() method.
Here is an example which demonstrates the tweening between two ColorMatrices (something that Grant Skinner demonstrated so elegantly with his ColorMatrix class already months ago):