I have to admit, I have mixed emotions about Christensen's return. I hope, GOD, I hope that not under the direction of Lucas, we get to see the actor shine in the roles of both Vader AND Anakin. At the same point, from a story perspective, I have to wonder how they're going to do this. If its primarily in the form of vision or flashback, I'm fine with that. If its more contemporary with the events of the series, Vader's "You should not have come back" line from ANH is intriguing enough for there to be a little follow-up, but will adding another confrontation between them muddy the waters? I'm sure these are all factors the creatives took into account when setting this up, but still... the question remains.