For most online services and products, reviews can be a one-sided affair; customers hold influence over businesses, for better or worse. But since its start in 2008, Airbnb's review process has been different: The guest (aka "customer") and the host (aka "business") both submit reviews, which means they can hold each other accountable for how good (or god-awful) an experience was. Infamous example: The orgy party from hell.