Although I mostly use Lightroom, I also have Capture NX and PSE6 (all Mac). Latest NX (version 1.3.5) works fine with my D300 files (indeed it came with that camera). PSE6 is still current on the Mac and works even with the latest ACR 5.4, that may be true even for the Win version, where PSE7 is current. Although I can't verify this, CS3 with ACR 4.6 should be able to work with D300 files - no need to upgrade to CS4 at all.
Did Ansel Adams' technical mastery make him a better photographer? Good question indeed. Fact is that with exposure his approach was very "raw-like". Measure dynamic extremes and overexpose/underdevelop accordingly - or whatever gave him best technical quality from the medium. This debate reminds me of the slide/negative dichotomy. One produces a finished picture, the other is meant to be processed and tweaked. Both are photography.