Echohawk
Shirokinukatsukami fan
I'm having a hard time seeing this as a slight against Eberron specifically. December was the last "Eye on Dark Sun" column too.I'm a bit surprised. I thought it had its fans but evidently not enough.
Several D&D Next columns and videos of panel discussions have intimated that the Forgotten Realms is, if not the default D&D Next setting, then certainly the one that they are focusing on initially. We also know there is a concrete plan to reboot the setting with the Sundering line of novels and adventures, so it isn't surprising that they are keeping up the online support for the Realms whilst dropping regular Dark Sun and Eberron support -- that's just where their focus is right now.
I think we'll probably still see sporadic support for other settings between now and the launch of D&D Next. WotC will also be getting some useful data from the PDFs sales as they make more campaign setting material from their back-catalog available. I reckon that'll also influence their decision on what setting specific articles to run in the online magazines.