The goal remains lofty: Airbnb wants to house 100,000 people in the space of 5 years. That's no mean feat, but the company has at least some experience in arranging these selfless gestures. It already encourages hosts to take in people affected by terrorist attacks and other incidents -- in a sense, this is the next logical step. There's no guarantee that this initiative will meet its targets, but it could serve as an important complement to official housing efforts if it catches on.