At a conference where I spoke recently, someone mentioned an organization who decided to drop their enewsletter in favor of RSS. I was really surprised by this and am not sure I understand (or would recommend) this strategy.
From my point of view, marketing in nonprofits (and business in general) today is about managing multiple platforms. I think that matching your message and its delivery to various channels is one of the most important skills for nonprofits to have. Using the same message across all media is not as effective as matching it to the audience. Your youth program participants may be on MySpace and your donors on Facebook, so modifying your message to these different audiences and the medium they prefer is essential. Although much of my work is around online fundraising and communications, I still believe in print. I think there is something about a print piece that people can pick up and peruse. If I am visiting someone's office I can't peruse the enewsletter you send them unless I snoop in their email.