Hi,
I am about to write a tool which would help indexing EPUB into ILSes.
My first guess is to produce ISO2709 or MARCXML record from EPUB files,
but since MARCXML or ISO2709 is not really what I would call the more 
portable (UNIMARC and MARC21 may both be handled in the same file 
format), I am rather considering producing OAI-DC or html5 +schema.org 
<http://schema.org/>+dublin corebut that would rely on EPUB3.

Any comment anyone ?
Has anyone considered such a tool ?
Is there any hidden corpse lurking around I should be aware of ?

Have a nice day

-- 
Henri-Damien LAURENT