Bingowings said:

DuracellEnergizer said:

As I hate the whole PT-spawned notion that only certain genetic supermen get to have an afterlife,...

Maybe only Jedi can see or hear them.

I think it is more about there being a connection between the individuals than anything else. Darth Vader/Anakin did not fade away like Obi-Wan and Yoda, yet he turned up as a ghost in the end scene of ROTJ.

In that scene, Luke sees Obi-Wan, Yoda and Anakin while Leia walks up to him and looks in the same direction and does not see anyone.