It's only free to another skype user. Normally skype is wifi only, this makes it possible to use on 3G. Going from a skype call to a landline/mobile is called 'skype-out' and is chargeable.
Theseand its only $3 a month for unlimited calls to US & Canada (no matter where you are). still a great deal
I don't know if that is Skype's fault.Yup - great deal. I believe I pay $8.40 every 3 months for my unlimited US and Canada plan. They do need to work on the quality though - it's not that great over 3G right now.