... but I will post in case this happens to someone else. I was sitting in a high back chair with my back to a window. When the light hit it just right, the ambient sensor picked it up and shut off the keyboard light. The funny thing is that I started moving my Macbook up and down and I noticed the keyboard kept going on and off and I am thinking "uh oh, loose connection." Not the case at all and everything is fine.
nmonti you are exactly right. Thanks for the quick reply!