With Commander 2013 released today but fully spoiled weeks ago and Theros already healthily in Standard, all eyes are on Born of the Gods and Journey into Nyx. Of the few things that are known about those two sets, one of them is the fact that they will continue Theros's dual land cycle with the remaining five two-color combinations split between the sets. Today, MTGSalvation.com Rumor Mill user deidarakoon posted a thread with some information that may pertain to that cycle:
So I went back to look at the Hero's Path page on WotC's site and noticed that they've updated it, featuring the leaked arts that we've already seen, and one which I don't recognize. On the last tab, the "Hall of Heroes" tab, I found this in the background. Not sure what it is, but I've never seen it before now. There also isn't any indication as to what set it's in, so that's why there's the [THS] tag.
As a context-free piece of unfinished-looking art, it's not clear what card this would be used for, if it is used at all (it may just be concept art), but it definitely has the hallmarks of the previous Temple land arts. It resembles an ancient Greek altar surrounded by classical arches, and there is a statue of, apparently, a god at the very top. The jagged lines that are visible on the image may be lightning - in which case, this is clearly the temple of Keranos, god of storms.