Merkel, who is expected to become Germany's first female chancellor later this month, and new Social Democratic Party (SPD) leader Platzeck are both 51 years old -- a decade younger than their party predecessors.
Both are trained scientists, both are Protestant. Most importantly, both of them grew up behind the Iron Curtain.
After Platzeck was named Wednesday to replace Franz Müntefering as head of the Social Democrats, the German press heralded the dawning of the age of the "Ossis" -- the colloquial term for east Germans.
"The generation of '68 has made way for the generation of '89," the left-wing daily Tageszeitung said on Thursday, referring to the year the Berlin Wall came down.
"A new trend has hit the nation. It's called Ossi power!" shouted the Westfälischer Anzeiger.
And Bild newspaper's front page screamed: "The Ossis are now the Bossies."
Irony of common roots
It said Merkel and Platzeck enjoyed the advantage of not having been brought up in the old German school of politics. "They had a life before the party and learnt to think in a different way politically."
The two politicians will work closely together to steer a so-called "grand coalition" of the left and right currently being negotiated after neither party managed to win a ruling majority in September's general elections.
The irony of their common roots was not lost on Platzeck, who told reporters: "We were assured by several Catholics from the Rhine area today that they could live with the sight of two Protestants from the East possibly signing the coalition accord, if it comes together.
"Germany will not fall as a result of this," he quipped.
Former powerbrokers shaped by left
Since Gerhard Schröder became chancellor seven years ago, the country has effectively been run by politicians whose ideology was shaped by the left-wing student movement that sprang up in Europe in 1968.
The figurehead of this generation was outgoing Foreign Minister Joschka Fischer, who was an activist in the early 1970s and was confronted four years ago with a photograph of himself beating up a policeman during a riot.
Merkel and Platzeck only began their political careers in 1989, cutting their teeth in the East German dissident movement that led to the fall of the Berlin Wall.
Bild newspaper on Thursday published black and white pictures of "the most powerful politicians in Germany" in 1990 when nobody could have guessed they would one day be known as such.
"A question of chance"
A bearded Platzeck was a member of parliament for the popular Alliance 90 movement and a mousy Merkel a spokeswoman for the last separate East German government.
But political analyst Oskar Niedermayer from Berlin's Free University said the pair's rise to power was "much more a question of chance" than a sign that East Germans were about to become the new political elite.
Eckhardt Rehberg, a lawmaker from East Germany for Merkel's Christian Democratic Union, used a football analogy to explain the situation.
"There is no 'Ossi quota' in politics, just like there isn't one in the Bundesliga," he said. "The league was made bigger at the start of the 90s to make place for the teams from the East. But today there are 18 teams in the first division and only one of them comes from the former GDR."
Apart from Merkel, the incoming government includes only two ministers who hail from the former East: the SPD mayor of Leipzig, Wolfgang Tiefensee, who will become transport minister and the CDU's Thomas de Maiziere who has been named Merkel's chief of staff.
Schröder's outgoing government counted only one Ossi, Manfred Stolpe, who served as minister for transport and the reconstruction of the East.
Until now the SPD's most notable East German had been Wolfgang Thierse, the speaker of the lower house of parliament, but he will be succeeded by a conservative from the West, Norbert Lammert, when the new government takes office later this month.