I have always maintained that if we attack Iran, there will be a furious amount of diplomacy going on behind the scenes between the U.S., Russia, and China - both of whom we would have to give up tremendous security issues to get them to covertly place their guarded blessings on a US/Israel attack on Iran. Right now, the stage is being set. Russia has sent tanks into Georgia LINK and have vowed to protect Russian interests and it looks as if a full-blown conflict/war could evolve from this situation, and the U.S. is currently backing Georgia. If this Iran attack does happen, you can bet that we will issue harsh warnings and a possible complaint through the U.N. Security Council, but other than that, our threats will be hollow. You have to give a little to get a little, and the dominoes seem to be falling into place.
So, here we go.
A war between Russia and Georgia (with Georgian forces having been trained by the US and NATO), a couple more carriers headed for the Gulf, and Israel and the certain elements in the White House (like Dick Cheney, who considers all of our military completely expendable in pursuing Israel's geopolitical agenda), itching for an opportunity to attack Iran before the end of this administration.
I don't know what the Vegas odds are about an attack against Iran, but I think it's a question of when - not if - such an attack will happen.