The new governments are essentially "coalitions of the willing," comprising parties who have at times been bitterly at odds and now find themselves in bed together.
The Greek Government includes members of the Socialist Party, the opposition conservatives and a fast-rising ultra-right party, LAOS.
These unnatural alliances will have a honeymoon for a while. But when the going gets rougher, the coalitions will be exposed to sniping from the powerful men they forced out - and who will claim the credit, saying they prepared the ground, even if the reforms succeed. And as both prime ministers are unelected technocrats, the governments will have poor legitimacy with the electorate. Yet early elections would revive the uncertainty that has so traumatised investors.
"If Monti fails, Berlusconi will attempt to convince voters that he is still the only possible 'saviour'," Andrea Mammone, professor of Modern History at London's Kingston University and co-author of Italy Today: The Sick Man in Europe, told the Herald. "In any case, the political game in Italy is still in progress."
It is one thing to pass an austerity law. But it is quite another to translate the text into practical measures to boost government revenue, cut state payrolls, liberalise the labour market and privatise state assets in countries that are notorious for civil-service bloat, political patronage, closed job sectors and tax dodging.
"Italy's problems will not go away with Berlusconi," said Vincenzo Scarpetta, an analyst at the London-based think-tank Open Europe.
"Berlusconi's personality has a role in this crisis, but it is definitely not the reason for the crisis. This is just the beginning, because now Italy needs to implement these reforms."
Greece's Government is even more hard-pressed. It has until December 15 to convince the EU and IMF of its earnestness in order to unlock a tranche of €8 billion ($14 billion) that will keep the country afloat. Under the scrutiny of these two bailiffs, it will then have to push through reforms in exchange for a second EU bailout of €100 billion in loans, €100 billion in debt reduction and a further €30 billion in guarantees.
In the meantime, public anger in Greece is unabated.
The main public sector has called a three-hour strike tomorrow night, in protest at rising taxes and 30,000 job cuts across the civil service. Demonstrations have also been scheduled for Thursday, coinciding with a meeting of EU finance ministers in Brussels..