Also a powerful media database. Nice is the option to support a server installation. Good also that it is a clean Mac OS X application. However, I find the user interface somewhat sparse.
A significant disadvantage is the small number of supported image formats - with my old DCS I'm stuck anyway, but other digital camera users will certainly miss one or another raw format.
Similarly, I find it rather disadvantageous that no information can be extracted from IPTC image data. Apparently only EXIF is supported - but professional cameras (especially the older ones) store image data in IPTC fields. All in all, I find iView Media Pro (see P2004) significantly better, especially the folder overview available in iView I find very intuitive. In Portfolio I have to work with searches and possibly then create collections from them - but these are static again, not dynamically adapting to new imports. Of course, this was only a quick test for me, so it's quite possible that some things are indeed possible, but the first impression is important to me - if I haven't used software for a long time (because I had no time for photography), I don't want to have to reread the manual...