Well, it's not quite a trend. But the victory of center-right candidate Gianni Alemanno in Rome last weekend has apparently been followed up by a victory for Conservative Party candidate Boris Johnson in London. Rome had been governed by center-left mayors since 1993; London has had an elected mayor for only eight years, and until this year no Conservative candidate was a serious contender. The London results are not in as I write, but you can find them at this website.
Both new mayors are colorful characters. Alemanno is routinely described as a "former neo-fascist"; he was a member of the Alleanza Nazionale and its predecessor the MSI. But he is no more of a totalitarian than his predecessor as mayor of Rome Walter Veltroni—the candidate of the center-left coalition that lost to Silvio Berlusconi's center-right in the April 13-14 elections—who was a member of Italy's old Communist Party. Both are now solidly respectable democratic politicians. Johnson has been busy as a member of Parliament and sometime editor of the Spectator from 1999 to 2005 and columnist in the Telegraph. His columns were often humorous and politically incorrect. But then the two-term incumbent mayor he has apparently ousted, Ken Livingstone, was politically incorrect in different ways: He lavished praise on Hugo Chávez and Fidel Castro and heaped obloquy on the United States. Livingstone nonetheless has had an interesting record as mayor, putting into place congestion pricing in central London (it costs you £8—$15.87—to drive over the line), encouraging commercial development, and preparing for the 2012 Olympics.