Stratfor has just published a shot review of the allegations. It concluded with the following words:
Iran has been known to carry out preoperational surveillance in the United States, but it has not yet used this intelligence to carry out a high-profile attack. It seems unusual that the Iranians would approach a Mexican cartel to carry out the assassination when the Iranians probably have the capability themselves. However, it could be that Arbabsiar and Shakuri were acting on their own, or that something unusual is going on within the Iranian government. Regardless, because Arbabsiar’s contact in Mexico was a DEA undercover source posing as a member of a Mexican cartel, at this point the cartels have not been directly linked to the plot.
It is unclear what the Iranians would have to gain by killing the Saudi ambassador to the United States, and the implications of the plot’s being linked back to Iran are huge. That makes the links back to Iran, which so far are only based on Arbabsiar’s alleged confession, seem exaggerated.
Coming from this normally rabidly pro-Israeli and GWOT-supporting "think tank" this is quite an expression of disbelief.
Amazing, Uncle Shmuel's lies are even hard to swallow for Stratfor....