You know, if you hadn't told me I wouldn't have known that there was a problem with the unfiltered shot. May be more apparent when blown up more. What ISO did you use on this shot?
I use the Noise Ninja plugin for Photoshop and it does pretty well without having to fiddle with a lot of settings. Here's a sample shot at ISO 1600 (100% crop). The first is the original, second is Noise Ninja and third is using Nik Dfine. I adjusted the settings to eliminate most of the color noise but left some of the luminance noise. What's left looks more like film grain, which doesn't bother me, plus it doesn't smear out all of the detail if you take it easy on the luminance.

- original.jpg (268.22 KiB) Viewed 214 times

- Noise_Ninja.jpg (201.89 KiB) Viewed 214 times

- Dfine2.jpg (207.09 KiB) Viewed 214 times