VZW purchased the 700MHz spectrum in the US for LTE rollout. 700MHz being a licensed frequency, moreso considering the FCC governs things in this country only. Therefore, VZW LTE = USA at this point.
I can't answer that question. To the best of my knowledge, VZW LTE coverage will be in the US only, but I could be wrong. As far as Skype goes, I don't know if you will be able to make video calls on 3G, or if it will be limited to 4G/WiFi only, so I can't really answer that one either.