It is not PC. Jews write God as G-d because it's believed that they are not to evoke his name directly.
-- I thought is wasn't a matter of evoking but rather the name of God cannot be destroyed or defamed. If someone types God and prints the paper out, the risk is that it can get thrown out or destroyed - typing G_d or G-d is to preclude the holy name from being thrown in the trash can (this is a paraphrase but this is the gist of it as I understand it).
Correct, more details halfway down the link.