The current "Arab Spring" uprisings against the unelected leaders that are so common in the Arab world have largely failed. In most cases, what made the difference was the security forces. If these soldiers and police were numerous, well trained and well paid, that was usually enough to keep the current despot in power.
For example, Algeria used a large and experienced paramilitary force to shut down demonstrations. In Bahrain, which was one of the more enlightened monarchies, paramilitary reinforcements from larger neighbors have suppressed most of the unrest. Bahrain has gone through this before, largely because a wealthy Sunni minority rules a much less affluent Shia majority. But that's how the largely Sunni population of Arabia prefers it (and why all Arab states long opposed removing the Sunni minority from control of the Iraqi government before 2003.)
Egypt appears to be getting a democracy, but they aren't there yet. The very corrupt bureaucracy and military officers still have their jobs. Just electing candidates who say they will clean things up does not guarantee that the powerful, and corrupt, families, bureaucrats and officers do not buy or threaten the new officials into backing off, or joining them on the dark side.
In Jordan, the monarchy had enough popularity, in the right places, to keep a lid on things. The Jordanian kings always paid close attention to the military, ensuring loyalty when it counted most. That's how it's supposed to be with a monarchy, but rarely is because of the unreliability of genetics in producing good rulers every generation.
Lebanon was on the verge of another civil war before all the unrest broke out.
Libya did careen into civil war, and this nasty bit of business may go in several directions before the violence dies down.
Syria is the most brutal Arab dictatorship, but the current government is trying to avoid a bloodbath. If that is not possible, there will most probably be blood. A lot of it.
Tunisia seemed to have overthrown it's dictator, but it's not over. For the same reason it ain't over in Egypt.
Yemen was never all that united, and has been getting less united for the last few years. The current pro-democracy unrest is more anti-corruption and "more for my tribe", and the current government is losing control of the security forces.