MediaBistro’s “EBookNewser” section has a brief writeup about HarperCollins partnering with NetGalley to make digital galleys and reader copies available, so that reviewers can download electronic copies.
While not every reviewer is going to want to deal with them, those who do like e-books will undoubtedly find them a lot more convenient than the piles of physical books they receive. And from the publisher’s side, it saves money printing and shipping them out; galleys and advance reader copies are generally more expensive per unit because of the small size of their print run.
Another advantage for publishers is that every e-ARC that replaces a print one is one more print book that won’t end up used at Amazon, eBay or a second-hand bookstore before the book’s actual publication date to “steal” a potential new sale—one of the points of contention often brought up in conjunction with Amazon’s used book listings.
Some people complain that publishers don’t seem to like e-books, but at least in this specific case publishers ought to love them.