Consider if you will the resources, the time and the financial investment given to attracting new web traffic. Banner advertising, link exchanges, search engine ratings, affiliate schemes and the list goes on. Yet when it comes to retaining a customer’s future business or even a return visit, we simply hope that they will opt-in to a newsletter mailing list and everything will be okay.Of course the truth of opt-in email marketing is far from okay. For a start, people, especially private indiv.