Skype alternatives: Gizmo, JAJAH, part 2

During Skype's recent outage, I mentioned Gizmo and JAJAH as alternatives. It seems that JAJAH did particularly well out of this snafu, as its registrations are reported to have gone up 50% since the event.

I think you know that I'm not suggesting that the majority of that 50% were readers of this weblog.