Effective Email

There is an interesting post over at Freakonomics titled "Surviving the Tyranny of Email". It reminded me of an article that a boss once gave me. So I did a quick search and quickly realized there is so much email advice out there that I probably wouldn't find the original article.
So why does it seem like everyone is still ignoring the usually good advice?
A few good links:

MindTools.com: effective email  

Forbes.com: effective email