Not according to the projections I have seen. They predict a cost per seat about the same a full-fair coach. Operating costs are around 60 cents per mile.
I can forsee even the company I work for that is very tight with travel dollars using this as a taxi service. We often send 3 or 4 people (engineers, marketing, sales) to a customer plant site. These places are often out of the way forcing several valuable employees to blow an entire day in airports waiting for flights, making connections at another ariport and then renting a car for sometimes a 100 mile drive to the final destination. With one of these puppies, they can skip the big airports and fly point to point to within a few miles of the final destination arriving in a few hours instead of facing an entire day of travel. The same could be said of vacation travlers. If say they wanted to go from NYC to Myrtle Beach for a few days of golf, they could be there in a couple of hours instead of blowing a day of their vacation at LaGuardia and Atlanta wating for the puddle jumper. Even if the cost is 50% higher than regular air fair, the time savings would be well worth it for millions of people.
I still don't see a big threat that corps are going to go into the airline business themselves in mass, but I can see the airlines using these jets to provide additional services.