Actually, character descriptions at
all are pretty sparse in Brandon's books.
To my (somewhat informed) understanding, Brandon likes it this way. He keeps description to a bare minimum as a way of encouraging the reader to fill out the character as much or as little as they need to. If a character trait (like hair or eye color) is important enough that it's relative to the story, he'll include it. Otherwise, it's left to the reader to imagine, and in a very real sense there's no way for you to be
wrong.
The fact that people rarely notice the lack of descriptors is a testament to his characters themselves, and the fact that good character development is more about what they do than how they look. Hell, I didn't notice myself until I began picking the books apart for illustration purposes.
He's become a bit more descriptive since he began writing WoT, but he still leaves a lot of it up to you. And I have a theory that suggests in doing so, he's encouraging readers to have a deeper relationship with his books. It's a good thing.