Normally, when the US announces they've caught or captured some terrorist, I assume either a) his next video will be out by August, or b) somebody else did the legwork, and the US is taking credit for it.
Such may be the case with Zarqawi. Apparently, he's been increasingly marginalized by the Shia in Iraq, and has responded by calling the US, Shia in Iraq, and Iran all conspirators in a plot to destroy Islam. Needless to say, this hasn't made him any friends.
So the fact that the US has announced his death should be taken to mean only one thing: If the US managed to catch or neutralize him, he was probably already irrelevant.
Of course, we can now expect all the right wingers to reset their "six more months" clocks, as Zarqawi's death will be seen to mark another "turning point" in this war. Of course, it's meaningless. I don't believe Zarqawi was ever the leader in the way the US believed he was - but the Pentgaon still doesn't want to accept the fact that Iraq is a full-blown anti-American insurgency, not some al-Qaeda plot.
(via Susie Madrak.)