If Izzie's not being "killed off" and if Denny's *not* a ghost, what's up with her storyline on Grey's?

Yeah, I didn't really get it either...I think thought that she'll be sick and killed off. She's gone way down in 'desirability' so they'll probably kick her off. Too bad, because even though people may not like her as a person, she's a good actress and I like her character on the show. Whatever I guess.