
Originally Posted by
Alex80
Usually in context where subject is described before. For example "В книге говорится, что ...." may be just "Говорится, что ..." if context implies already that we are talking about this book. So, "говорится" alone usually is not replacement for "Говорят" in role of "they say".
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")
There may be cases when "говорится" is used interchangebly with "говорят" in role of "they say", but they are rare and exist somewhere between 2 cases above.