You're going to get a lot of answers to this one
Discussing raw conversion choices, as one guy once said, can be like discussing religion.
I prefer Nikon software products (Capture NX2) for anything involving skin tones.
With landscapes, while I still tend to use NX2 the most, I also like PhotoNinja (which seems to just have that extra special "something" that the others lack). Capture 1 is worth a look as well.
That being said, Nikon software is strangely designed, sometimes buggy, and slow. I run more of a high quality / low volume thing, so this aspect doesn't bother me, but if I were a wedding or event shooter, I'd probably look at Capture 1 or a very carefully done camera profile in Adobes Lightroom.
Only Nikons software truly and completely understands Nikons "Picture Controls" settings. I will warn you that if you do intend to try the Nikon software, be aware, at least in my opinion, that Nikons default choices for their picture controls, well, they suck. I've long been running with a customized picture control (done via the picture control editor in View NX2 or Capture NX2) instead of using the canned "Standard" picture control. This aspect of things is why some folks really don't like the OOC colors from Nikons, me thinks - if a Nikon user is running an un-modified "Standard", expect slightly garish skin tones and too much midtone brightness. Just my thoughts anyway. Raw converter preference tends to be hugely personal, and it's probably best to spend some time with the usual and popular suspects (plus PhotoNinja) and see what works best for you.
-m