It's not that business travelers have chosen to shun Airbnb -- in fact they make up a decent chunk of the short-term subletting business. But now the startup is making a concerted effort to lure those customers in with Business Travel on Airbnb. It's dedicated portal with tools specifically designed not just for travelers, but for companies to manage employee travel. The company has even partnered with Concur, which builds travel and expense systems like Triplink, which is used by a vast majority of Fortune 100 companies. Not every listing will be displayed through the new portal. Odd ball listings like tree houses will be filtered out, as will any shared rentals -- such as a room in a larger apartment. Courting business customers is going to be essential for Airbnb to continue to grow. And considering how much money investors have pumped into the it, growth is certainly high on its list of priorities.