ID:278213
 
For those of you interested in seeing what HTML5 means for the simple stuff, read through the rather long http://diveintohtml5.org/semantics.html . It's a great read that really breaks down the essentials of outlining in a human readable format. If you're HTML knowledge is low to begin with, you can learn a lot about the proper formatting of pages in HTML generally, and why the formatting is important.
Cool. I'm only halfway through it, but it's definitely a good read. About time they simplified doctype.

I've never paid particular attention to link relations, because I rarely see them in action, but I guess I could start using them in the hopes that browsers will implement some sort of interface to take advantage of them, particularly next, prev, and up.

I wonder if "But I referenced a legal page with rel="license"!" would hold up in court, if the license went beyond basic copyright. :P

In response to DarkCampainger
DarkCampainger wrote:
I wonder if "But I referenced a legal page with rel="license"!" would hold up in court, if the license went beyond basic copyright. :P

Of course not. The rel=license links could, however, be used to configure a browser to display a warning in the corner when the page you're viewing is not liberally licensed (GNU FDL/AGPL, CC-BY(-SA), etc).

The link types also help search engines make sense of your page, so it's worth using them just for that.
In response to Ryan P
Pretty much all of those tags are there to help computers understand the context of your page. Search engines, screen readers, and browsers are the ones that will get the most out of them.

Search engines can more easily understand the content, context, and time period of your information. Screen readers can read a page in a way which is more understandable to the sight impaired. Browsers can reformat pages to better fit their owner's liking.

Of course, this also helps the site designers, who can more easily identify blocks and decide how they should be placed and how they should look, rather then what to name them and how to define stylesheets.