Quote Originally Posted by Alex80 View Post
However there is "Как говорится - ...." which contains some (usually well-known) fact. It is replacement of "Как говорят - ...". You use it then you want to point on this fact, for example, while saying proverb. "Как говорят/говорится - всяк кулик своё болото хвалит." = "As was said - every bird likes its own nest." (maybe I should use "As it is said, ..." because "It was said" more likely to be "Сказано")
I would add that in English, "It's said, that..." and "They say, that..." are more or less interchangeable when quoting a traditional proverb or "scientific wisdom"-- but "they say..." sounds more natural when you're quoting gossip:

It's said/they say that "Too many cooks spoil the broth." (~ У семи нянек дитя без глаза -- "With seven nannies, no one keeps an eye on the baby.")
It's said/they say that birds evolved from two-legged carnivorous dinosaurs resembling a miniature T. rex.

BUT

They say that Tom Cruise is secretly gay! ("It's said..." -- это не ошибка, а тут звучит чем-то не идеально, ИМХО.)