anakin is the first dark jedi to ever return to the light side.. that has to count for something as far as being a "ghost" goes. in order for a jedi to appear in the afterlife, he must "kill himself" kinda, like obi-wan did. you also see yoda disappearing when he dies. what puzzles me though is that anakin doesn't disappear when he dies, his body if burnt. that is the only thing about the end of return of the jedi that doesnt add up. then again, even though we're used to think of luke as the big jedi, anakin was indeed the "chosen one" in the prophecies. that, too, has to cound for something lol.