Stumbled across a cool editing technique this evening by accident!
I took a few pictures lastweek with my 50mm 1/8 with a macro tube wand a new light ring I recently got for doing portraits and macro stuff and was editing the images in Lightroom 3 and clicked the Black and White option accidentally.......
I found that I could edit options like sharpness and then just flip it back to colour with a touch of a button, in all a hell of a better way to edit non colour settings of a image.
Would be interested to hear if anybody has done this before or what your results are like when you try it.
The only way I can think of doing this in Photoshop is to duplicate the layer of your image, desaturate it then record a action of your adjustments then play the action back over the original image.
My final result is attached.