Back in the 2003-2005 era of the web, the big debate always seemed to come down to the argument of whether or not content was still "king". Some would argue that keywords, inbound links, and other factors far outweighed the importance of good content. Others would argue that other things might be important, but all the traffic in the world from those other things wouldn't amount to a hill of beans if there wasn't good, compelling content at the landing point.
In The New Fundamentals, we talked a bit about how the Internet has evolved and how the very nature of the content has grown beyond text to include videos, images, maps, news, and more.
Even though content and how we access it has evolved, we also took a look at how the basic fundamentals of how we get the stuff indexed so it can be found has really stayed the same. Sure, there are little tricks - little bits of finesse - that we can toss in on top of the foundation. We'd be silly if we didn't experiment and see what other little things can be added to the basics.
A Coney Island Hotdog is built on top of a classic and solid foundation - but with that meatsauce and cheese, it becomes so much more than just a Hot Dog. 
The House On Top of the Foundation
In the early says of SEO, we submitted our sites to the DMOZ to give it the best launch punch. This is great for text, but what about the new content types?
For Google, we can pretty safely make the assumption that uploading your video to YouTube and giving it a good description, title, and keywords is a good start.
For images, we might take a look at Flickr for storage of some or all of our images.
With a bit of research, you can also self-host your things and do quite well at getting it indexed directly. From what I can see, the YouTube and alternate hosting methods are good ways to get things picked up faster for newer/lower clout sites, but once your site is established, it's probably easier to manage and makes little overall difference if you host everything yourself. Images can be hosted locally regardless - they seem to get picked up so long as you link them, get proper alt and title text and so on.
As you expand to different content types, the basic fundamentals are all the same - but each different type of content is going to have a few different tips and things to truly optimize it. The same is true with textual copy - what we have talked about in this article are just the basic building blocks. Doing the things we've talked about are a good start, but...
There is a Lot More to SEO Than Just the Basics
The reason that SEO seems so much like some sort of magic cauldron that your specialist tosses ingredients into and waves a magic wand over is because that's sort of what it is. It's magic - assuming that you are of the mind that magic is merely science that we don't understand (yet).
SEO is a delicate blend of the fundamentals we have talked about here; site mechanics, information architecture, internal and external linking strategies, and literally hundreds and hundreds of other factors. Another thing that makes SEO tricky is that the little things - those things you do to go that extra mile from "good rankings" to "top rankings" changes about 10% more quickly than you can learn it.
By the time you test, master, and implement some new technique, it's power to do its job will already have changed somewhat.
These are the reasons why I always stress the "big picture" and "diverse strategy" things. If you have pages that are ranked because of specific factors that you have used to launch your page to #1, that's fine until the ranking algorithm changes in a month or a year. If your foundation and other factors aren't solid, the page isn't going to just go down in ranking, but it will likely go way down. This is why you need to both A) understand the basics and B) understand or have someone on staff who is constantly keeping up with the new and evolving advanced concepts that take you to the next level for ranking and conversions.
SEO is a Team Sport
One of the biggest things that is often overlooked in SEO is that people tend to isolate these efforts into its own entity.
While it's true that someone must oversee and stay on top of the SEO efforts, it is of critical importance that everyone who does anything with the site at least understands the basics as it relates to their specific task. Your copywriters are wasting everyone's time if they write their articles and then send them to the SEO people to rewrite for search engines. The programming department is wasting energy if they add or create something, then the SEO team comes in later and says, "No, you have to link it this way and generate URL's this way and..."
You really only need one person on staff who can comprehend and see the big picture of how everything relates to everything else. But everyone on the staff needs to do a little research. Copywriters should be required to read tweets, forums and blog posts by SEO Copywriters (start with someone like @karonthackston and take a look at some of the people they follow). Developers should do the same with tech oriented SEO people (like someone like @RuudHein and some of the people he follows).