Most of the article really talks about how to successfully get an email of a person who has already landed on your landing page/podcast page/affiliate/blog etc. but how to get those people there in the first place is a bigger challenge. Also, one of the ways you can include in your list is by offering free tools/widgets. For example, OpenSiteExplorer by Moz is a great example. Evergreen and very useful for the target audience.
The huge advantage of email over social media is that prospects and customers are more likely to see an email than social media. Just posting something doesn't mean that everyone you want to see your message will see it. Your post might not even show up in your targets' social media streams. However, an email will sit in the inbox until it's read (or deleted).
It's practically impossible to overstate the importance of direct mailing lists to the success of your direct mail program. The correct mailing list will contain your most valuable prospects. The more careful you are in analyzing and selecting direct mailing lists, the better your chances for success. There are several different categories of mailing lists available on the market today ranging in cost and appropriateness for your market. When you are considering what type of mailing list to buy consider the following three types: