The Arab dictatorships, at least the softer ones, have a hard way ahead. Tunisia's Ben Ali collapsed, Egypt's Mubarak gave up.
Tunisia and Egypt are not really short term threats to Israel, though. Tunisia never was and Egyptian economy will soon collapse because of the lack of tourists. And in the event of an Islamist wave in the country, it will lose also foreign money. In this case, this will have an effect on the US elections. Who will vote for someone who abandoned an ally (OK, a dictator) for an Islamist regime? Of course foreign policy have little effect on the US elections, but Obama is not so popular and this effect my be enough to change the result of an election.
In any case, if Egypt is not a menace for Israel, it is not so for the Hezbollah regime that holds Lebanon hostage, and of course the other proxies of Iran, in Gaza. But this is not a new menace and it is doubtful they will start a full war with the UN troops still in the area.