The Guardian reports:

Ben Ali had taken refuge in Saudi Arabia, at the end of an extraordinary day which had seen the declaration of a state of emergency, the evacuation of tourists of British and other nationalities, and an earthquake for the authoritarian politics of the Middle East and north Africa.

After hours of conflicting reports had him criss-crossing southern Europe by air, the Saudi state news agency confirmed he had arrived in the kingdom together with his family. Earlier, French media reported that Nicolas Sarkozy had refused Ben Ali refuge, although France denied that any request had been received.

In Tunisia, prime minister Mohamed Ghannouchi announced that he had taken over as interim president, vowing to respect the constitution and restore stability for Tunisia's 10.5 million citizens. "I call on the sons and daughters of Tunisia, of all political and intellectual persuasions, to unite to allow our beloved country to overcome this difficult period and to return to stability," he said in a broadcast.

Opposition sources say, however, there is great uncertainty as to what will come in the immediate aftermath,  There is also some concern that Ben Ali might return before elections are held.
The septuagenarian strongman has been power since 1987. While nominally democratic and usually politically placid, Tunisia has been rocked by protests over the last month. Thousands have crowded into the streets and faced police gunfire to protest high food prices, unemployment and rampant government corruption and cronyism. The Christian Science Monitor reports:

Protests in Tunisia erupted last month when Mohamed Bouazizi, a young unemployed university graduate from Sidi Bouzid, doused himself in gasoline and lit himself on fire in front of a local government building. Unable to find work in the formal sector, he had taken to selling fruits and vegetables informally but then police confiscated his merchandise and reportedly slapped him in public. His self-immolation was apparently an act of final despair. He died Jan. 4.

Ben Ali's fall comes one day after U.S. Secretary of State Hilary Clinton warned Arab states that they risked "sinking into the sand" if they continued to ignore high-level corruption.

The collapse of Ben Ali's regime is also sending shocking waves throughout the region, a stark warning to other autocratic regimes that the social peace might be paper thin.

“Tunisia is a warning for the Egyptian regime,” says Diaa Rashwan, an analyst at the Al Ahram Center for Political and Strategic Studies in Cairo. “It's a warning, and any rational regime would take action to address it. But I don't think Egypt has any strategy for addressing it.”

Al-Jazeera has full coverage.

This video report from PBS.