They will likely be flying small propeller planes, which many people don't like... props make sense for these short routes though because they are often faster, based on the fact that there is less time for takeoff and landing (they don't spend as much time "reaching altitude")
I also don't like that they are trying to bootstrap based on folks buying these subscriptions which they have yet to launch, and that they plan to launch in a month. Very pyramid-scheme-like.
I would love for it to work, but I just can't see this business model surviving. It reminds me a bit of independence air and Dayjet, both of which lasted less than a year.
Also, this doesn't inspire confidence: https://twitter.com/#!/PlaneRed/status/93572991077715968