As property listing sites go, Airbnb did not produce any true innovation. And although they clearly must have done some things really well to generate so many people using their service(a.k.a. probably taking them out of craigslist), the really true 'innovation' they did was getting away from abiding regulation.
Now that they are big, they are going to cooperate as much as possible to build regulatory walls so that another Airbnb wouldnt be able to show up and contest those rates.
I have the same feeling from Uber/Lyft. The traditional taxi service is terrible for drivers, and they present true benefits to them: but only because they found a way to bypass the law by paying with the apps instead of giving money to the driver. (If I made a site on my own, and picked up people from the street and the gave me money in hand, i would be breaking the law).
Now that they are big enough, they can also influence the rules enough to make it harder for future competition.
These strategies can only work when the companies get big enough to influence the law making, or when they have such a strong market dominance(or monopoly) that they can now afford to abide by the rules (or to make them).
So, in terms of Airbnb , the only innovative thing they did was finding a law loophole. Woohoo.