The key to internal linking is... wait for it... organization. Now you may not think of that as the "fresh perspective" we promised, but think of it this way; the reason that you don't hear many people talking about the importance of internal linking structures is because most SEO endeavors are not nearly as organized as they are needed to be in order to achieve high rankings.
What are internal links?
The links that are traded between the pages of your site, of course!
Many SEO's agree that an individual page's importance is measured in many respects by the number, the importance and the depth of other pages on the site that refer (link) back to that "individual page".
Think of it this way; a website for a syrup farm in Vermont wants its homepage to rank high for the search phrase "
Maple Syrup Tours in Vermont". It has a simple one-step registration form on the index page for tours and the
title tags have been properly optimized. The website has hundreds of content pages regarding "the types of Maple Syrup in Vermont" that it grows at its syrup farm but none of those pages link back the right way (with anchor text) to the page the website owner wants Web visitors to see - the place where the registration form is actually located - the home page. If the website owner were to link to this page from secondary (or tertiary) pages with the keywords that convey that the home page is a place of great interest when it comes to "Maple Syrup Tours in Vermont," the home page (the one with the registration form) would achieve higher rankings.
Confusing? Don't worry, all you really need to do is be organized enough to know the keywords that you want your site to appear under, create content pages that link back descriptively to the page you want to receive visitors at from popular search engines.