Replying to @Patrick Murray-John's post:
Patrick, I love Anthologize and would personally love to see multimedia support. I'll file a ticket! I don't know how common multimedia ebooks are -- as you can tell, I'm still figuring this whole ebook thing out -- but what I'm hearing from grad students is something along the lines of, "I have this awesome [public domain] work that I know better than anyone else in the world, and I'd really like to create an ebook that's enriched with multimedia annotation." I'm wondering how I can help support this.
I really like the idea of going from WordPress, which a number of grad students are already familiar with, to a multimedia-enhanced Anthologize ebook.
And thanks again, all. This has really helped me figure out which questions I need to be asking about which technologies. Googling was leading me down too many garden paths.