They have given us some other surprises lately, too:

Chinese Test Anti-Satellite Weapon

China 'hacked' into Pentagon defence system

I think this incident was just an underlining of certain points they probably told Robert Gates in Beijing this last week.  Perhaps something like, "We'll help you put some pressure on Iran, but you'd better lock up your other silly ideas and put them in indefinite storage."

Looks like someone got the message:

But there has been no new buildup of U.S. firepower in the region. In fact there has been some shrinkage in recent months. After adding a second aircraft carrier in the gulf early this year -- a move that Secretary of Defense Robert Gates said was designed to underscore U.S. long-term stakes in the region -- the Navy has quietly returned to a one-carrier presence.

<...>

At the moment, there are few indications of U.S. military leaders either advising offensive action against Iran or taking new steps to prepare for that possibility. Gates has repeatedly emphasized that while military action cannot be ruled out, the focus is on diplomacy and tougher economic sanctions.

The article also confirms that it's the military that has the sanest assessment:

The man whose responsibility it would be to design any conventional military action against Iran -- and execute it if ordered by Bush -- is Adm. William Fallon, the Central Command chief. He is playing down prospects of conflict, saying in a late September interview that there is too much talk of war.

"This constant drumbeat of conflict is what strikes me, which is not helpful and not useful," Fallon told Al-Jazeera television, adding that he does not expect a war against Iran. During a recent tour of the gulf region, Fallon made a point of telling U.S. allies that Iran is not as strong as it portrays itself.

"Not militarily, economically or politically," he said.

Fallon's immediate predecessor, retired Army Gen. John Abizaid, raised eyebrows in September when he suggested that initiating a war against Iran would be a mistake. He urged vigorous efforts to stop Iran from acquiring nuclear weapons, but failing that, he said, "There are ways to live with a nuclear Iran." He also said he believed Iran's leaders could be dissuaded from using nuclear arms, once acquired.