Manifest prints a list of people on the skydive, and the guys who drive us to and from the landing zone make sure everyone gets back. They don't really do a roll call though, they just know everyone.
It's still a good idea to carry a cell phone with you in case you land way far out. Most of our out landings are in one field or the other to the side of the landing area. In the one field, your punishment for landing out is having to land in cow shit. Hope you're good at stand up landings!