Punctuation question

[Lauren]

> From: Gene Kim-Eng

> Nothing new about that.  The colon was always "formal,"
> vs comma "informal."  What has changed is that during
> the past few decades (I'd say more like 30-40 years)
> there has been a relentless march toward "friendly
> informality" in all walks of life in the US, including 
> business.  Whether this represents a good or bad thing
> is another question.
> 
> Gene Kim-Eng

Dear Mr. Kim-Eng:

Would you say that your view of colon use suggests that whether to use a
comma or colon depends on the tone the correspondence is intended to convey?

Sincerely,
Lauren