Dire Bare
Legend
My FOGS (favorite online game store) has an interesting entry in their catalog for this year, though it's probably not for 4e and it's not on Amazon or WotC's product catalog: Forgotten Realms 25th Ann. Edition
If done well, this could be really cool! I hope this rumor turns out to be truth. Seems too late for 4E, but too early for 5E . . . but a Realms setting book could easily just skip the rules bits as the D&D core rules cover it pretty well. I think the only thing 4E Realms introduced to the game was the Swordmage/Bladesinger and Genasi, both of which "should" have been in the core rules anyway. Not sure that anything truly Realms-specific was introduced in 3E either, except perhaps the backgrounds (which could have/"should" have been a magazine article instead).