I'm currently using Reunion 9, but it annoys me enough that I keep looking for alternatives, including online options. Unfortunately, Reunion seems to implement more of my "must haves" than any of the other options I've looked at.
I want to like MacFamilyTree. I actually started with it but found it too limiting. The new photo tagging stuff in 5.6 is nice though. My biggest gripe against it are that it won't import my Reunion gedcom file without throwing away data. All my custom formatted sources lose most of their data and any tags it doesn't understand are ignored. Throwing away data is an unforgivable act. At least put it into some note field so I can deal with it. Still, the program seems to be evolving quickly and I'd like for it to win me back.
I love Reunion's ability to customize events but the single window with modal dialog approach to editing is awfully cumbersome and since everything is driven from the family group window, adding the same source or photo to multiple people is tedious. But it works, it's been reliable. It just irritates me.
I'd love the ability to geocode events (and make use of geocoded photos) as well as face tagging but until an app gets the genealogy right and has robust gedcom handling, it doesn't matter.
I've tried demos of a couple of other programs including some windows apps, but nothing has encouraged me to switch.
What apps are the rest of you using?