The "title" in the <head> is now the canonical location where the book title should be stored. Including an <h1> at the beginning of the <body> is now optional. htmlbook-xsl logic for EPUB updated accordingly, to look for title in <head> first and then in heading child of <body>.
Merge pull request #86 from oreillymedia/xmlschema

Updated book title requirements in XML Schema and corresponding XSL handling for EPUB