Aperture
It would be nice to try it out in person, but looking at the screenshots and video tours Aperture appears to be a nice combination of the strengths of both iPhoto and iView MediaPro, with some unique features on top. I particularly like the virtual 'Light Table', and the ability to compare two images side-by-side at a reasonable resolution. Why has no-one thought of that before? The archiving facility also looks excellent and very easy to use. The editing and retouching features look like they are more advanced than those in iPhoto, and would probably be perfectly adequate for my needs, though I'm sure that the real professionals would still need Photoshop for editing and retouching. It's quite pricey, but as a lecturer in Higher Education, I can get an almost 50% discount on it. Which is nice.