So, they claim that all calls from US/Canada to US/Canada numbers (landline or mobile) will be free. And, sure enough when I tried to call my home number earlier this morning it rang.
Next I tried calling a Canadian number that was in my contact list: Call failed. So, I tried a US mobile number. That worked. I delete the contact from my list and try again, but it still knows the name I had associated with the number. Exit Skype and restart it. Now I can call the number in Canada. Annoying, but I guess it was free (the quality was pretty poor too, although the call to the US number was OK, so perhaps that was a problem at the other end, which happens to also be a VoIP service number).
A couple of hours later I try to make another call to a US landline: Call failed. So, I retry the call to my home number: Call failed. I don’t even know for certain whether people could have called me; since I could not call out, perhaps I was actually off the network?
Conclusion: I will stick with GizmoProject, which has worked flawlessly for me on Linux and MacOS as well as with hardware ATA and SIP phones. It might not be free to call US numbers, but at least I know the call will connect, and the voice quality will be acceptable. I keep seeing people in the Gizmo forum claim that Skype is better, but I’m not seeing it. Coupled with all the problems its architecture can impose (you give them permission to use your computer and bandwidth when you sign up), I don’t see any reason to stick with Skype.
My conversations usally failed when I use skype.