IMO.
This [link|http://www.washingtonpost.com/wp-dyn/content/article/2007/01/02/AR2007010200557.html|Washington Post] story mentions his campaign's claim that the document was pilfered from some luggage that was missing for a few days. If that turns out to be true, it may backfire on whoever took it.
All of the stuff in that document would have come out anyway. It coming out now lets him claim that it's "old news" when he gets asked about it.
Rudy has a lot of skeletons, but so did Bush. Whether he has a chance depends on his competition and how nasty the campaign is.
It's still way too early for something like this to have much of an impact on the real campaign for 2008. And you don't really think that Bush (or any other president) personally carries the [link|http://www.globalsecurity.org/wmd/systems/nuclear-football.htm|Football] around with them, do you? ;-)
Cheers,
Scott.