Meir Dagan, head of Israeli intelligence spoke about Iran today. The bottom line: "The reality in Iran is not going to change because of the elections." He said it was "unlikely" that the situation would actually escalate into a revolution. I give significant weight to what Dagan says, since Israel is known to have pretty good intelligence on Iran. We can always hope that the clerical regime collapses, but no one should be holding their breath waiting.
The Mossad leader also estimated that Iran would be able to produce a nuclear weapon by 2014. But as the article points out,
The Mossad is credited with delaying Iran's nuclear program by years. Defective equipment and defective plans sold to Tehran through straw companies in Europe have reportedly set back the Iranian nuclear program substantially. Reports have attributed mysterious deaths among key figures in the program to the Mossad.Hopefully these efforts will continue to have success. A military strike is not in the U.S. interest at this time, and with the U.S. resolutely opposed to such action, I believe that an Israeli attack isn't in Israeli interests either. Sabotage, selective assassination, and other forms of disruption and delay are their best options.