James Joyner at OTB: 
Not surprisingly, perhaps, most bloggers on the Right, such as Jules Crittenden  and Dan Collins , think Hersh is crazy as a loon while most on the Left, like Marcy Wheeler , Kathy Kattenberg , and “Jill Hussein C.”  believe all this is not only plausible but likely.
Hersh is a loon. Always has been. This point is so well known it amazes me anyone’s willing to sign his paychecks anymore.
Let’s get to it: Hersh pointing to someone who was actually assassinated would be helpful. Does anyone think that if the left actually had anything of the sort, we’d not have heard all of this already, in wall to wall mode on CNN and MSNBC? We have not. We’re supposed to think this moron Hersh has some special path to information that all these other leftie sources have not? Sorry, no sale.
There’s this, too… Hersh coming up with a named source would be not only helpful, but unusual to the point of being bloody well miraculous. Absent either of those things, what we have, is Hersh trying with his usual ineffectiveness to remain relevant by telling the whackjob left the anti- Bush/Cheney fairy tales they want so desperately to hear.
And when even Willis (possibly the least honest blogger on the planet second only to Glenn Greenwald) is a skeptic, you know there’s a serious credibility issue.