This is a topic that will continue to be important in the future. If you are going to sell products or whatever online, you have to write good e-mails. If you you do this right, you will reach your customers, you get their [tag]attention[/tag] and they will [tag]trust[/tag] you. But if you don´t write good e-mails you will not only lose one sale, but they might never buy from you ever, because they will not even open your [tag]e-mail[/tag]. It´s all about trust.
This is why a post over at Lifehacker is such a good read, the original content is at Email: an author´s guide.