Der Spiegel reports that American officials have been briefing NATO countries, particularly Turkey, on possible military action against Iran's nuclear program. (I can't get data to load from the Der Spiegel site, but here is a piece from Captain Ed with extensive quotes and commentary.)
That this is being publicly discussed strongly suggests that the attack is not imminent. Rather, this is a way to signal to Iran that the time for games has passed. Iran seems to have gotten the message, suddenly agreeing last week to let Russia process their uranium fuel instead of doing it themselves, as they previously were dead-set to do. I doubt that their own enrichment program will shut down entirely, but Iran will probably try to keep it off the radar for the time being. At least until they think they can get away with it again.
I am still pessimistic. Barring a fundamental change of Iranian government, I think any leader will be too strongly tempted by their nearly complete nuclear program to restrain themselves for long. But assuming that the mullahs regain their sanity, we may have just pushed off the day of reckoning for a time. Or, we may have finally decided to lay it on the line, which is probably better in the long run.