Thought i'd chime in on satelite internet:
My mother uses DISH service at her home, with WiFi for the internet. When i visit there i can log into SL easily, and travel inworld just fine- as long as i stay within close range of the router. I haven't had much issue with lag- i can visit inworld clubs and dance with music enabled.. (whereas sometimes with my UVerse at home, i get lots-o-lag.)