it is good to know it is good for me to know 分別？

It is good to know your own weaknesses. = 知道自己的弱點是好事(人人皆適用, 對我對你都是好事。)
it is good for me to know my own weaknesses. = 知道自己的弱點對我來說是一件好事。(強調自己。)

簡單嚟講，It is good to know比較general，所以比較常用(google search 有成20,400,000 results)
而it is good for me to know針對個人，比較specific (google search 有4,140,000 results)

This is just used to tell others what is our main point.
In your example,
'It is good to know' mean know this is always good
''It is good for me to know'' mean I am just talking about myself

It is simple!
Just like the different between these two:
John's mother can cook well
Mother can cook well

本人認為頭一句子"It is good to know" 祇是上文而已;其義思是"知道就好了"代表上文;而應該繼續有下文.
至於第二句子 "It is good for me to know" 這句子也是上文而已;其義思是"我知道就好了",而應該繼續有下文.
Yip

這件事是值得讓人知道的
這件事讓我知道是正確的（好的）

It is good to know.（適用對象是任何人）＝To know is good for everyone.
It is good for me to know.（適用對象只限我一人）= To know is good for me.
it是虛主詞，不定詞to know是delayed subject（延遲的主詞）

it is good to know 帶有你的意味存在
例如
It is good to know the information.
對我受用，同時也建議你可以去了解這個訊息

It is good for me to know the information.
這個訊息我來說很受用，強調"我"
但你不一定適合

Hope it is useful.

有me 就只有你知道，沒有me 就人人都知道