I made a really nice skin smoother project file for AE cs3. It works really good. It has a test tint to see mask. It simply isolates the red channel of sat, lum, contrast to key a mask for smart blur. Looks very natural. Finally no more roto!
just use the matte adj controls inner/outer sliders to matte for the smart blur output. You can set it for blue and do fast sky replacements, no roto. Guess where I got inspiration from? andrew kramer.