There's a major difference between the behavior of leisure and business travelers. Leisure travelers have (historically) been price-sensitive in the extreme. Business travelers have been way more schedule- and airline-sensitive. This is why you see so many perks thrown at business travelers (free upgrades, etc.)—it's an attempt by the airlines to win the business of their most profitable clients.

As to whether airlines will be inspired to install more wi-fi, consider this: all the major US airlines that don't already have wi-fi on their entire fleet have announced plans to install it on a lot more of their fleet this year. They're hoping people—especially business travelers—will make their purchasing decisions on the basis of wi-fi.