This is a stage-managed DRUDGE spectacular. We need to be smart about things like this, so caution is key. I have no inside info whatsoever, but here's my first-reaction analysis based on what's out there so far:
This is something ABC has and nobody else has, or else it wouldn't be a story. This is something ABC decided not to air. Why wouldn't they air something so newsworthy? DRUDGE will say media bias, but given Dan Rather's troubles isn't ABC's caution about some video they were sent suggestive?
So this is probably going to be something they were sent that's fake, hence their decision not to publicize it. But of course they would have turned it over to the govt, and the govt would happily leak it to Drudge. (Or the scammer who sent it to ABC in the first place would leak it to Drudge.)
Keep in mind that all "legit" terror videos so far have been sent to Arab media first, not ABC news.
If it's a Rove production this should be a well-made item, but it will be too clearly designed for an American audience. (Or it could be something really lame like a video of some random insurgent in Iraq bragging about attacking America)
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The info is up now. It's as I thought. ABC cannot authenticate it. The CIA has it. Our own government probably leaked this info to Drudge. http://www.drudgereport.com/abct.htm