I switched to Capture NX2 right when it first came out. What used to take me an hour in photoshop I could do in less than 2 minutes with Capture NX2. Now the other photo processing programs (photoshop included) are getting much better at rendering an as shot photo so process time with them has been greatly reduced. If fact they have gotten so much better that I don't use NX2 hardly anymore. I have switched to Lightroom 4 - mainly for the database functionality but have learned to really like the develop module. When I was using NX2 I would also use photoshop along with it for finishing the photo and printing. How that I am using lightroom 4 I hardly ever use photoshop.
So is it a better product? Yes and No. It is better in how it interprets the raw files but has a lot less functionality than photoshop. I don't think I could use just Capture NX2 without some of the processing having to be done in photoshop.