Active D-Lighting doesn't do anything that you can't already do in Aperture (or Lightroom or similar). All it does is to reduce contrast in the highlights (depending on the strength of the highlights) so all (or at least more) of the detail can be fit into the 8-bit JPEG. Your RAW processor will let you control highlights to the same degree (and may, in some cases, read the "ADL Strength" tag in the NEF and adjust the default image adjustments).

What the ADL will do for you when you're shooting RAW is adjust the histogram and highlight warnings on the camera, which are based on the JPEG that results from your conversion settings (Optimize Image/Picture Control/ADL/White balance). That will give you a better idea of what levels are being recorded in the NEF (and, of course, what the resulting image will look like if you make the same adjustments the camera makes). Without ADL, the highlight warnings will turn on at lower levels, which may lead you to reduce exposure, potentially damaging the shadow detail in a high dynamic range scene. (Conversely, it can lead to slight overexposure decisions in flatter scenes, such as portraits, unnecessarily adding to post-processing time and effort.)

So while ADL may have little actual affect on what APerture presents to you, it's still a good guide for shooting RAW in landscapes, architecture and similar scenes.