Just spoke with my sister in Holland on the N80i using TruPhone. Crystal Clear quality. Our 10 minute and 33 second call cost $USD 0.37 I can see how this can get addictive. Great quality (better than Skype - sounded like a local call), easy to make calls and with a familiar phone interface unlike Skype!
Hmmm who needs a limited device like the Sony Mylo when you have easy to use VoIP with the N80i and Truphone. Don't forget too that the N80i has the flexibility and openness of Series 60 along with many 3rd party apps unlike the closed Mylo!
Need to try lots more calls e.g. to South Africa and China but Truphone feels like a killer app for WiFi phones!