Despite his desire to fight this disease, Robert Jordan was much aware of his illness and the potential possibility he would not survive it. While book 12 remains -at this time - unwritten, he began a detailed instructions on how that final book in the Wheel in Time series would end. Additionally, he also has detailed papers on the two prequels he was planning to write.
And from what I've heard from various sites, he had already selected the writer who would finish book 12, plus write the two prequels.
So his legacy will continue, but don't expect that final book for some time.
On a personal note, I gave up on the series long ago. I've tried to get through book 4 at least three times, but found all the characters -especially Rand - to be annoying and felt, at times, that they all deserved to die.
I remember her from a memorable guest shot on the original Battlestar Galactica. But with the passing of Charles Nelson Reilly and now her, another memorable, in your face funny face has left the world. She was one of kind.