But is WotC really interested in D&D books in gaming stores? I doubt so, if they were, they would be putting out books at rate they did in 3e/4e times. I believe 5e is The Placeholder Edition, out there merely to keep the "product zero" alive so that WotC can license the hell out of it and have relatively easy income without all the hassle.
Of course, at this point most retailers are overjoyed, because finally they have The Most Popular P'n'p RPG back on their shelves and the publisher isn't trying to work around them. But what will happen in a while, if D&D release schedule is pretty much "2 super adventures per year, zero splatbooks"?