APP with media/docbook

After hearing Tim Bray's talk at OSCON on APP as the glue of the web, 
I'm rather sold on using Atom for our internal publishing API. This is 
especially relevant as we're in the midst of dealing with content 
loading issues between our separate disparate internal content 
repositories.

First, our primary format for content is Docbook. From my understanding 
of the Atom Publishing draft, its possible to include the entire 
Docbook XML under its namespace within an Atom entry content element. 
It's also possible that we could POST the whole thing as 
application/xml and consider it 'media' (which would make it easier on 
some of the client systems as they wouldn't need to make an Atom XML 
entry). Is it 'bad form' to be POSTing Docbook XML as a media resource?

Second, the Docbook content is loaded with figures and images. The 
current process as I understand it for loading in content with media 
resources is:
1) POST all the media images, track the Location supplied
2) Edit the content referring to them, to refer to the new Location's 
in step 1
3) POST the new Atom entry referring to the media resources

Is this the primary way people are currently loading documents with a 
lot of associated media are doing it?

Finally, is it still valid to upload a base64 encoded image as an Atom 
entry content? This was in an earlier spec of the APP I believe, and 
made it easier to upload images and such while including a decent 
amount of associated metadata.

On a side-note, are there any client validation bots out there yet that 
will retrieve an APP introspection document and do some crawling 
through the content to see that the server is implementing the APP spec 
properly?

Thanks for all the hard work on these protocols, I'm really looking 
forward to being able to use them heavily.

Cheers,
Ben