Aperture is a much smoother, smarter version of iPhoto ... I like it a lot, and use it as my primary post-processing tool, together with Noise Ninja for handling noise reduction, especially from my GR-D II.
l'm leaning toward getting it, as l do minimal manipulation. interesting that you need another app for noise reduction...is the Noise Ninja a freeware app? l'm not familiar with it.
None of the main software seems to be as good as the specialised noise reduction stuff.
