Best place to socialise in Rome is in front of the Gregorian. With Rome's crazy traffic and services on the brink of collapse, we all meet at the Gregorian's bar for a cheap lunch. Having grown up in sacristies, one of the great joys of my life has been priestly camaraderie. It's been said countless times: the priesthood is the world's greatest fraternity.
Notice, too, the old "placet" and "non placet" they kept in the aula magna? Catholic culture lives!