I think fear is the wrong word for it personally. Am I concerned with the potential? Absolutely as should be any reasonable person in my opinion.
As I would love to hold complete confidence in my abilities to raise perfect, healthy chickens, the fact remains that they will be semi free range and therefore exposed to insects and birds that may carry disease. I live right in a migratory path as well so it's important to pay attention.
The cases started in China not too long ago, spread to India, then Africa, Canada and recently there was a case in Oregon of a "backyard" flock of chickens testing positive for the avian flu, it's spread far quite fast so it serves the homesteader to be aware and informed.
I use a great tool for gathering worldwide information quickly and easily, after all how can one claim to be informed without all the information?
http://hisz.rsoe.hu/alertmap/index2.php
Unfortunately H5n8 has reached California not too far from my town, and considering how restaurants and freight companies are not within my control I have made the informed decision to stay away from fowl for a while, as well as being critical about keeping my future flock as safe as possible (On that subject any effective natural antibiotics for chicks? Will echanchia benefit their immune systems perhaps?)
That being considered I say manifest the most positivity you can, but it's careless to disregard these concerns.