Thanks Humbrie, I am familar with Seb's model as I was in the audience at this talk.
Our current thinking around hypermedia is we want to enable it and are deliberately supporting it in the design. We are not opinionated however on how you do it. Over time we may offer add-on solutions that you can use (but are not forced to use).
The way to do that injection in web api is through formatters or operation handlers. With formatters you do it for a specific media type. OR's support for custom formats is currently limited, but it does support XML as far I understand through XPATH.
With web api you can represent links any way you want to using any rendering format i.e. json, xml, or link headers and can inject them in several ways.
1. You can write formatters that support embedding links. Those links can be embedded as link headers or within the response body. Today getting access to the response in the formatter to modify the headers isn't easy but we will be fixing that.2
2. You can write an operation handler that takes the return value of the operation and adds links to it before it hits the formatter.