I believe social media (Facebook, Twitter, etc.) is replacing blogging as the primary way web users share links. Most social media links are no-followed and have little or no explanation surrounding the link to add context. These kinds of links are not as strong of a signal as a 1-2 paragraph blog post that links to a great article or piece of content.
My random SEO theory: Search engines (especially Google) will assign more value to sites/pages that continue to link out and provide them with this dying signal of quality. In other words, linking out to other sites — already a Good Thing — will become a Better Thing over time.




