All this ensures is that the media will run a lot stories about a dirty campaign intent on stealing the election. Given that the Clintonites are going to need some good will in July (if in fact they want to garner a delegate majority through superdelegates), the logic of this ploy eludes me.
Sounds like time for some idle speculation! I was having lunch today with a friend who's convinced Clinton will be the Democratic nominee. He believes the superdelegates will decide that at the end of the day, they'd rather have a candidate willing to hit John McCain below the belt. I think it's unlikely Hillary Clinton will get the nomination because of "good will" towards her on the part of the superdelegates--that ship has already sailed (or, at least, is pulling up anchor and readying for departure). Her best bet is probably to convince superdelegates hungry to take back the White House that she, and only she, will do whatever it takes to win a bitter, hard-fought election. Thus, even if they don't damage Obama per se, running nasty ads and murmuring about going after elected delegates reinforce the message that this is who you want on your side in a knife fight.
(Or, I suppose, we could just be reading too much into one line in the middle of a Newsweek interview...)