Email authentication has an impact on email delivery. And it's well on the way to achieving the critical mass that allows all ISPs to start acting on non-authenticated email.
So if you are, like the author of this article, in a state of either denial or ignorance (or both) when it comes to email authentication, certification, accreditation and reputation, then you should definitely read Mark Brownlow's article. It outlines what it's all about, why it's important for email marketers, how it works and what you need to do about it.
Bottom line: if you aren't already, you need to start working on implementing authentication standards for your outgoing emails now. The success of your email campaigns depends on it.
Want to get your hands dirty immediately? Then I advise you to read this article on email authentication mistakes and misconceptions as well.