Performance: I use an Intel 3, 4GB RAM, speedy hard-drive, good FX card, and Windows 7, 32 and 64-bit editions. I didn't notice any speed differences between Capture and View NX2. It takes me about 8 seconds to Convert an NEF to a JPG. I think about the same 8 seconds to save edits to an NEF as well.
I use View NX2 and do any editing in my favorite editor (Photoshop, only because I know it. You can get GIMP for free!). Capture NX2 does not give enough fine grain control if I'm going to edit, and I am comfortable with advanced masking and editing techniques. Capture NX2 is super easy to work with if you aren't savvy with editing software and want quick results (for example: make a person more fleshy looking if white-balance changes won't do it).
So what does Capture NX2 offer? High-quality D-Lighting.
View NX offers D-Lighting HS. "High-speed" D-Lighting can add substantial noise but I use it regularly only at the setting of 1 (so unlikely noise issue), which essentially expands the histogram of color levels to fill the possible color space, instead of bunching up and peaking values in only a small intensity). Essentially, it will make sure your darkest colors are closer to absolute black, and your lightest colors are closer to absolute white. This can increase contrast but will generally give you better dynamic range. Woohoo!
Capture NX2 also has a Noise Reduction tool that is quite nice if you have a high-ISO shot and want to try to smooth gradients or edges out. I found this to be superb to Photoshop (but I did not try Noise Ninja or other software). If you like high-ISO shots, this is a great feature.
Capture NX2 has recatlinear image correction to get rid of your barrel distortion or lens deformation. This is also pretty nice.
I am not a professional. So if I eventually am discovered and need to showcase my photos, I'll consider going back, buying Capture NX2 and re-editing the pictures I have. For now, I'm pretty content with View NX2 and a photo editing application.
Capture NX2 feature set is here:
http://www.nikonusa.com/Nikon-Products/Product/Imaging-Software/25385/Capture-NX-2.html
Sorry I did not find a View NX2 set for comparison.
I hope this was useful to somebody out there!