In the wake of massive protests in Tunisia that brought about the fall of leader Ben Ali and similar protests currently threatening incumbent Egyptian President Hosni Mubarak, many are asking: who's next?

Reporting from on the ground in Egypt, even CNN correspondent Ben Wederman mused:

#Tunisia ousts Ben Ali. #Egypt ousting Mubarak. What next? The old #Arab order, the faux Pax Americana, are collapsing. Buckle up. #Jan25

With high unemployment, poor job prospects, and food insecurity fairly standard across the region, many are looking to other vulnerable countries across North Africa and the Middle East for similar unrest.

The Wall Street Journal predicts unrest in many Arab and Persian states:

Meanwhile, other American allies in the Middle East stand to be weakened by political unrest of their own. Current and former U.S. officials specifically cite Jordan, the Persian Gulf emirates and Saudi Arabia as vulnerable to political agitation.

The Standard & Poor’s rating agency said it does not expect "a wave of regional political instability," but said that "political and fiscal uncertainty" threaten the sovereign ratings for several Middle Eastern and North African countries.

Egypt, Algeria, Jordan, and Morocco were among the countries cited as “more susceptible than others.”

But most eyes have turned to two Arab states: Jordan and Yemen.

JORDAN

With a rising defecit, rising inflation, high unemployment, and high poverty, Jordan is looking exceptionally vulnerable as popular protests sweep Egypt.

The Associated Press reports that conditions are ripe, but Jordan's King Abdullah might be in a stronger position than Ben Ali or Mubarak:

After two weeks of widespread protests inspired by the revolt that overthrew Tunisia's autocratic president, Abdullah has promised reforms in meetings with members of parliament, former prime ministers, civil society institutions and even Jordan's largest opposition group, the fundamentalist Muslim Brotherhood Movement.

"The government buys cars and spends lavishly on its parties and travel, while many Jordanians are jobless or can barely put food on their tables to feed their hungry children," said civil servant Mahmoud Thiabat, 31, a father of three who earns $395 a month.

Such complaints mirror those that ultimately led to the downfall of Tunisian President Zine El Abidine Ben Ali, though as a monarch with deep support from the Bedouin-dominated military, Jordan's ruler is not seen as vulnerable as Tunisia's deposed leader.

YEMEN

Tens of thousands of protesters have been taking to the streets of Yemen's capital, Sana'a, in the wake of the fall of Tunisia's Ben Ali.  Protester's have been making deliberate references to Tunisia and Egypt, with some shouting "Yesterday, Tunisia. Today, Egypt. Tomorrow, Yemen." 

The Washington Post reports that the economic conditions are ripe for mass protests, but the social and political infrastructure might be lacking:

President Ali Abdullah Saleh, who has ruled Yemen for 32 years, is clearly rattled by the anarchy unfolding in Egypt. But what has happened here also shows that Yemen's situation is distinct from its neighbors, even as many Yemenis share the same grievances and frustrations driving the upheavals in Egypt and Tunisia.

Many among the Arab world's dispossessed hope for a domino effect that could see more of the region's autocratic regimes fall, like the swift collapse of the Soviet Union. But in Yemen, activists are facing numerous obstacles, straddling political, social and economic fault lines, even as they gain courage and inspiration from the momentous events unfolding in the region.

Social media is used less frequently and widely than in Egypt, and the political opposition is fractured.

Yemen and Jordan are seen as the most likely candidates for replicate protests, but observers are reluctant to project unrest to the degree seen in Tunisia and Egypt.