Comment Some more detail over at undeadly.org (Score 5, Informative) 162
You will find more details over at the OpenBSD Journal site (undeadly.org), specifically the stories KARL - kernel address randomized link and the followup Kernel relinking status from Theo de Raadt. These and other items will also turn up on the project's Innovations page.
And for that whirlwind tour of what's good in that system, take a peek at my OpenBSD and you slides.