From the latest Barnes & Noble Press email I received:
eBook Pre-Order no longer requires a placeholder interior file, so you’ll never have to worry that readers will receive anything less than your finished project once it’s ready for release.
This is good news. One reason I’ve personally avoided pre-orders has been the need to provide an interior file. I haven’t felt that the risk of a distributor sending out a file not meant for distribution is offset by the benefits of having a pre-order available. But I also haven’t wanted to tie up a ready-to-publish book in a pre-order, so I haven’t used pre-orders at all.
Smashwords has allowed an asset-less pre-order for a while (as of 2015, in fact), but I just haven’t felt it was worth putting up a pre-order in only one venue. Now here’s another.
This might be the year I finally do some experimenting with pre-orders.