“Go to faeries for gossip about vampires, to werewolves for gossip about faeries, and do not gossip about werewolves, because they try to bite your face off: that was Magnus's motto.”

As quoted in The New Speaker's Treasury of Wit and Wisdom (1958) by Herbert Victor Prochnow, p. 190
As quoted in ...
Variant: The only time people dislike gossip is when you gossip about them.

Quoted in Gert Jonkers, "Gore Vidal, the Fantastic Man," Butt, No. 20 (7 April 2007)
2000s

1920s
Variant: No one gossips about other people’s secret virtues.
Source: On Education, Especially in Early Childhood (1926), Ch. 2: The Aims of Education, p. 50
Context: The instinctive foundation of the intellectual life is curiosity, which is found among animals in its elementary forms. Intelligence demands an alert curiosity, but it must be of a certain kind. The sort that leads village neighbours to try to peer through curtains after dark has no very high value. The widespread interest in gossip is inspired, not by a love of knowledge but by malice: no one gossips about other people's secret virtues, but only about their secret vices. Accordingly most gossip is untrue, but care is taken not to verify it. Our neighbour's sins, like the consolations of religion, are so agreeable that we do not stop to scrutinise the evidence closely.

Right Wing Women, ch.2 (1978)

Quoted in Gert Jonkers, "Gore Vidal, the Fantastic Man," Butt, No. 20 (7 April 2007)
2000s
Context: Everybody likes a bit of gossip to some point, as long as it’s gossip with some point to it. That’s why I like history. History is nothing but gossip about the past, with the hope that it might be true.

Cecil Graham http://books.google.com/books?id=8SzYgCNz-vwC&q="Gossip+is+charming+History+is+merely+gossip+But+scandal+is+gossip+made+tedious+by+morality"&pg=PT52#v=onepage, Act III
Variant: Scandal is gossip made tedious by morality.
Source: Lady Windermere's Fan (1892)

Source: Julian

Source: Gossip Girl