Ahh ... yeah, familiarity with Riverworld is hardly a necessity.  Basically yes, people keep being brought back, usually in a fashion similar to either how they arrived, or the moment of their death.  So, if you drive a car at 200 mph off a cliff ... you will probably wake up after a short time somewhere ... in a parked car.  But if you abuse this and go on a binge of suicide you may not wake up again.