Cost would have to be competitive with Metro but I would pay a bit more for the convenience.
I think that the fun factor is the bigger selling point over convenience.
It does sound like they will have separate buses for each stop, although for a place like Arlington they may want to consider making two or three stops along the Orange line corridor, and even for the other stops further out they may find it easier to fill the buses if they make more than one stop. I'd be a big fan of taking a bus if I lived close enough to a stop where I could walk home.
