I just got word that Topaz Labs has released an update for their popular NR tool "DeNoise v4.1"
The most significant improvements in v4.1 are:
improved processing speed - 100% increase for many configurations.
Better color handling - improved color edge recovery, new Clean Color slider.
Interface and preset improvements.
I have confirmed the above mentioned.
Denoise has just stepped it up a notch imo.
The program has just gone from potentially good to, amazingly good!
http://www.topazlabs.com/downloads/index.php?d=denoise