I suppose I should say that it's mostly "the usual suspects" --- people who, for the last ten years or so, have accused the United States (and particularly Bush) of everything from creating a "Reichstag Fire excuse to destroy civil liberties" to "invading to seize the Afghan oil" (hint: there isn't any). And of course the 9/11 Truthers.
In large part, the current outcry seems to be a move to try and exonerate bin Laden (usually via one or more of the above routines) in order to claim that his killing was of an "innocent man" and that we should all REALLY HATE AMERICA for his death. To a lesser extent, there's a demand that there be no celebration or exultation because either/and:
A) No one should ever cheer for the death of another human being and you are horrible for doing so
B) Osama will just be replaced, so nothing's been accomplished
C) He's now a martyr, killing him just means Al Qaeda will REALLY get SERIOUS NOW and start blowing up half the planet.
At what point did people decide it was a bad thing to celebrate the death of someone who directed the hijacking of civilian jetliners in order that they be plowed into buildings full of civilians? How about those of these types who believe BUSH was the one who arranged it all --- the ones who want him put on trial, found guilty and hung from the neck until dead? Can we expect that they would actually treat the event of Bush's death (even from an accident, such as getting hit by a bus) as anything short of a reason to scream their joy to the heavens?
To me, all of this comes across as Extreme Sour Grapes. America can't be cheered for, even if Obama's in charge now and personally ordered the hit to go ahead, because it is now ingrained in them to hate anything America does in the Middle East. Admitting something good and right was done is anathema. It must be attacked, denied, because doing otherwise enters a grey area where America is Not Entirely Evil.
It is this disassociation from real facts, the promotion of preferred mythology over substance, that many of the same people are quick to assume on the part of their opposition, and which ironically helps feed their willingness to widen that disassociation on their own part.
It is like watching half the world slowly go mad with rage.