I was lucky to go to a recent Vincent Versace Nikon Masterclass in San Francisco. He has written books on Photoshop CS, but has now switched over to Nikon Capture NX as step one for his D2X/D200 work, following this with CS as necessary. Here's Versace's URL:
http://www.versacephotography.com/v2/gallery/index.html
I downloaded the Capture NX and got hooked. I've no financial attachment to any of this. The work flow has become play flow. Have fun in any case. Nikon has helpful tutorials here:
http://www.capturenx.com/ - Bob