What was her constant, rapid, and strange blinking about? And that chewing? Weird! I think it was Mad Cow Syndrome.
I suspect she was wearing contacts lenses. Frequent blinking is very common.
The mouth movement looked to me like she had a hard candy or mint in her mouth and was moving it around.
Did anyone notice when Bush turned to shake her hand, which turned into a double handed embrace by Nancy that when Bush tried to let go, his hand somehow ended brushing her lapel. Almost like Nancy was bending over for a hug. I thought for a minute she might be trying to give him a handful of her chest and embarass him.