Having only the paperback version of The Way of Kings in my current collection (I'll be sure to get it in hardcover sometime nearer the end of the series), I was curious if it had artwork like the Words of Radiance does on its interior, so I looked up the images online on Brandon's site.
And I came across these:
http://brandonsanderson.com/images/wok/tWoK_ENDSHEET-FRONT-1-webres.jpg
http://brandonsanderson.com/images/wok/tWoK_ENDSHEET-REAR-2-webres.jpg
I realize that there's probably been talk, debate and questions asked and answered already about this second one, as the first is obviously the double eye of the Almighty with the ten surges and ten orders of the radiants surrounded by the ten heralds. But, after some thinking about it, I've been wondering if this shows ten Parshendi forms, each somehow having access to two different aspects. The two on the red gem might somehow be the voidbringer forms of the Parshendi.
However this is speculation, and I'm most likely wrong.