Saturday, December 10, 2011
When you think about this, it* doesn't make much sense. It says that the EPUB and MOBI versions should have a different ISBN. But EPUB and MOBI are mostly interconvertable (it's basically a reformatting -- the same HTML and CSS is there) and do the same things (EPUB is a superset, really). Suppose you have an Android tablet and you get an EPUB ebook. In the software of the tablet one could have an embedded converter — like calibre calibre-ebook.com — that automatically converts the EPUB to a MOBI and you could be reading the ebook in a MOBI reader on that device vs. an EPUB reader on the same device that would look the same. Would you expect to see the MOBI ISBN on the copyright page or the EPUB ISBN? Only a fairly simple software transformation has been made.
Also I just got an ebook from Smashword smashwords.com and I got them in a bundle of formats: MOBI, EPUB, PDF, RTF, PDB, LRF, ... . What this recommendation says is that each one gets a different ISBN. (This was not the case, of course. It was the same ISBN on both the EPUB and MOBI versions, just as you would expect.) If someone sells their ebook in a bundle of formats like on Smashwords then there should be a different ISBN on each format? I don't think so.
I think the confusion is that the electronic world is not the print world. Just because there are different ISBNs on hardback and paperback (and those two from ebook), that analogy doesn't go over into the e-world since different e-formats can be automatically transformed from one to another, possibly in the reading device itself.
So the recommendation of different ISBNs for EPUB and MOBI is a bad one.
* Re the Book Industry Study Group (BISG) proposal for ISBNs and ebooks, via the post When Book Publishing Gives You ISBNs, Make ISBNade by Thad McIlroy.
What I think will happen in practice for an e-publisher who is EPUB-based is that they would be able to sell their ebook (.epub) in the Nook Store, iBookstore, Google Bookstore, etc. with the ISBN (eISBN) they assigned to that ebook, but when it came to putting it in the Kindle store would let Amazon put an ASIN on it (as Amazon continues to be outside the EPUB standard).