I've just formatted my first ePub ebook & would welcome any comments that anyone has about formatting, presentation, etc. Can't do anything about the content, I'm afraid!
I've tried it on ADE on Windows, on Stanza on the iPod, and on Bookworm on the web. Bookworm ignores all the CSS, of course, but otherwise everything seems normal.
The basic question - whatever reader you're using -
does this look like an ebook to you?